error.h: drop trailing comma in enum

In C++'98/03, trailing commas in enumerations are not allowed, but have
been introduced in C++11. This patch drops the trailing commas in order
to avoid compiler warnings (e.g. GCC with -pedantic).

See #9 and http://code.google.com/p/rapidjson/issues/detail?id=49 for
previous instances of this issue.

include/rapidjson/error/error.h

@@ -85,7 +85,7 @@ enum ParseErrorCode {
     kParseErrorNumberMissExponent,              //!< Miss exponent in number.
 
     kParseErrorTermination,                     //!< Parsing was terminated.
-    kParseErrorUnspecificSyntaxError,           //!< Unspecific syntax error.
+    kParseErrorUnspecificSyntaxError            //!< Unspecific syntax error.
 };
 
 //! Result of parsing (wraps ParseErrorCode)