Allow the Thrift compiler to be built without the Python generator.

- Use AX_THRIFT_GEN to make configure support --disable-gen-py
- Update the compiler Makefile.am to exclude the generator.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665614 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/configure.ac b/configure.ac
index e03675c..6c9e4a4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -132,6 +132,8 @@
 AM_CONDITIONAL([THRIFT_GEN_java], [test "$ax_thrift_gen_java" = "yes"])
 AX_THRIFT_GEN(csharp, [C#], yes)
 AM_CONDITIONAL([THRIFT_GEN_csharp], [test "$ax_thrift_gen_csharp" = "yes"])
+AX_THRIFT_GEN(py, [Python], yes)
+AM_CONDITIONAL([THRIFT_GEN_py], [test "$ax_thrift_gen_py" = "yes"])
 AX_THRIFT_GEN(cocoa, [Cocoa], yes)
 AM_CONDITIONAL([THRIFT_GEN_cocoa], [test "$ax_thrift_gen_cocoa" = "yes"])
 AX_THRIFT_GEN(st, [Smalltalk], yes)