THRIFT-1681: Add Lua Support Patch: Dave Watson

Github Pull Request: This closes #92
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 26d9020..0ff7fa0 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -74,6 +74,9 @@
 SUBDIRS += nodejs
 endif
 
+if WITH_LUA
+SUBDIRS += lua
+endif
 
 # All of the libs that don't use Automake need to go in here
 # so they will end up in our release tarballs.