[Transport] Deprecate non-functional AqueousTransport class

This class has been broken since 2009. Note the vectors m_visccoeffs,
m_condcoeffs, and m_diffcoeffs, which are used but never initialized.

include/cantera/transport/AqueousTransport.h

@@ -97,6 +97,7 @@ namespace Cantera
  *  In the second part, a mixing rule is applied, based on the
  *  Wilkes correlation, to yield the mixture viscosity.
  * @ingroup tranprops
+ * @deprecated Non-functional. To be removed after Cantera 2.2.
  */
 class AqueousTransport : public Transport
 {

src/transport/AqueousTransport.cpp

@@ -36,6 +36,8 @@ AqueousTransport::AqueousTransport() :
     m_debug(false),
     m_nDim(1)
 {
+    warn_deprecated("class AqueousTransport",
+        "Non-functional. To be removed after Cantera 2.2.");
 }
 
 bool AqueousTransport::initLiquid(LiquidTransportParams& tr)