Fixed an error that turned up in VC++.

I think the problem was that VC++ didn't allow friend functions to be
defined in the body of declarations in .h files.

Cantera/src/Group.cpp

@@ -21,8 +21,6 @@
 #include <algorithm>
 #include "Group.h"
 
-#include "Group.h"
-
 namespace Cantera {
      
     /**
@@ -73,4 +71,14 @@ namespace Cantera {
         return s;
     }
 
+    std::ostream& 
+    operator<<(std::ostream& s, const Cantera::Group& g) {
+	    if (g.valid()) {
+           s << g.m_comp;
+	    } else {
+           s << "<none>";
+        }
+        return s;
+    }
+
 }

Cantera/src/Group.h

@@ -13,7 +13,9 @@
 #define CT_RXNPATH_GROUP
 
 #include "ct_defs.h"
+#include "ctvector.h"
 
+using namespace std;
 namespace Cantera {
 
     /**
@@ -117,16 +119,11 @@ namespace Cantera {
 
         ostream& fmt(ostream& s, const vector<string>& esymbols) const;
 
-        friend ostream& operator<<(ostream& s, const Group& g) {
-            if (g.valid()) 
-                s << g.m_comp;
-            else 
-                s << "<none>";
-            return s;
-        }
+        friend std::ostream& operator<<(std::ostream& s,
+                                        const Group& g);
 
     private:
-        vector_int m_comp;
+		ctvector_int m_comp;
         int m_sign;
     };