[Thermo] Make continuity check for enthalpy dimensionally consistent

All quantities here are nondimensional, so taking h+cp*T makes no sense, and
caused the test to pass even for suspicously discontinuous thermo data (although
the bad data would generally get flagged by the tests for cp and/or s).

src/thermo/NasaPoly2.cpp

@@ -21,7 +21,7 @@ void NasaPoly2::validate(const std::string& name)
 
     // enthalpy
     delta = h_low - h_high;
-    if (fabs(delta/(fabs(h_low)+cp_low*m_midT)) > 0.001) {
+    if (fabs(delta/cp_low) > 0.001) {
         writelog("\n\n**** WARNING ****\nFor species {}, discontinuity"
                  " in h/RT detected at Tmid = {}\n", name, m_midT);
         writelog("\tValue computed using low-temperature polynomial:  {}\n", h_low);

test_problems/VPsilane_test/output_blessed.txt

@@ -1,21 +1,39 @@
 
 
+**** WARNING ****
+For species SI2H6, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  19.8328
+	Value computed using high-temperature polynomial: 19.9055
+
+
 **** WARNING ****
 For species SI2H6, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  49.5493.
-	Value computed using high-temperature polynomial: 49.7214.
+	Value computed using low-temperature polynomial:  49.5493
+	Value computed using high-temperature polynomial: 49.7214
+
+
+**** WARNING ****
+For species SI3H8, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  29.3028
+	Value computed using high-temperature polynomial: 29.4297
 
 
 **** WARNING ****
 For species SI3H8, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  65.9731.
-	Value computed using high-temperature polynomial: 66.2781.
+	Value computed using low-temperature polynomial:  65.9731
+	Value computed using high-temperature polynomial: 66.2781
+
+
+**** WARNING ****
+For species SI2, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  74.0115
+	Value computed using high-temperature polynomial: 74.0387
 
 
 **** WARNING ****
 For species SI2, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  32.8813.
-	Value computed using high-temperature polynomial: 32.9489.
+	Value computed using low-temperature polynomial:  32.8813
+	Value computed using high-temperature polynomial: 32.9489
  
   silane:
  

test_problems/cxx_ex/output_blessed.txt

@@ -41,22 +41,40 @@ Chemical equilibrium.
 Equilibrium composition and pressure for a range of temperatures at constant density.
 
 
+**** WARNING ****
+For species SI2H6, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  19.8328
+	Value computed using high-temperature polynomial: 19.9055
+
+
 **** WARNING ****
 For species SI2H6, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  49.5493.
-	Value computed using high-temperature polynomial: 49.7214.
+	Value computed using low-temperature polynomial:  49.5493
+	Value computed using high-temperature polynomial: 49.7214
+
+
+**** WARNING ****
+For species SI3H8, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  29.3028
+	Value computed using high-temperature polynomial: 29.4297
 
 
 **** WARNING ****
 For species SI3H8, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  65.9731.
-	Value computed using high-temperature polynomial: 66.2781.
+	Value computed using low-temperature polynomial:  65.9731
+	Value computed using high-temperature polynomial: 66.2781
+
+
+**** WARNING ****
+For species SI2, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  74.0115
+	Value computed using high-temperature polynomial: 74.0387
 
 
 **** WARNING ****
 For species SI2, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  32.8813.
-	Value computed using high-temperature polynomial: 32.9489.
+	Value computed using low-temperature polynomial:  32.8813
+	Value computed using high-temperature polynomial: 32.9489
 Output files:
   eq1.csv    (Excel CSV file)
   eq1.dat    (Tecplot data file)

test_problems/silane_equil/output_blessed.txt

@@ -1,18 +1,36 @@
 
 
+**** WARNING ****
+For species SI2H6, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  19.8328
+	Value computed using high-temperature polynomial: 19.9055
+
+
 **** WARNING ****
 For species SI2H6, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  49.5493.
-	Value computed using high-temperature polynomial: 49.7214.
+	Value computed using low-temperature polynomial:  49.5493
+	Value computed using high-temperature polynomial: 49.7214
+
+
+**** WARNING ****
+For species SI3H8, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  29.3028
+	Value computed using high-temperature polynomial: 29.4297
 
 
 **** WARNING ****
 For species SI3H8, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  65.9731.
-	Value computed using high-temperature polynomial: 66.2781.
+	Value computed using low-temperature polynomial:  65.9731
+	Value computed using high-temperature polynomial: 66.2781
+
+
+**** WARNING ****
+For species SI2, discontinuity in h/RT detected at Tmid = 1000
+	Value computed using low-temperature polynomial:  74.0115
+	Value computed using high-temperature polynomial: 74.0387
 
 
 **** WARNING ****
 For species SI2, discontinuity in s/R detected at Tmid = 1000
-	Value computed using low-temperature polynomial:  32.8813.
-	Value computed using high-temperature polynomial: 32.9489.
+	Value computed using low-temperature polynomial:  32.8813
+	Value computed using high-temperature polynomial: 32.9489