Added -Wreserved-id-macro and but exclude existing nonconforming macros (#141)

Added -Wreserved-id-macro and but exclude existing nonconforming macros
diff --git a/GTMDefines.h b/GTMDefines.h
index 8ec88cc..7feb1cb 100644
--- a/GTMDefines.h
+++ b/GTMDefines.h
@@ -109,6 +109,10 @@
 // been placed in.
 //
 
+// Ignore the "Macro name is a reserved identifier" warning in this section
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wreserved-id-macro"
+
 // We only define the simple macros if nothing else has defined this.
 #ifndef _GTMDevLog
 
@@ -170,6 +174,8 @@
   #endif  // __has_feature(c_static_assert) || __has_extension(c_static_assert)
 #endif // _GTMCompileAssert
 
+#pragma clang diagnostic pop
+
 // ----------------------------------------------------------------------------
 // CPP symbols defined based on the project settings so the GTM code has
 // simple things to test against w/o scattering the knowledge of project
diff --git a/XcodeConfig/subconfig/General.xcconfig b/XcodeConfig/subconfig/General.xcconfig
index 781c414..a62dcf6 100644
--- a/XcodeConfig/subconfig/General.xcconfig
+++ b/XcodeConfig/subconfig/General.xcconfig
@@ -117,7 +117,7 @@
 //                           same selector rendering this mostly useless to us
 
 // C Only Warnings
-GTM_GENERAL_OTHER_CFLAGS = -Wdiv-by-zero -Wbad-function-cast  -Wnested-externs -Wold-style-definition
+GTM_GENERAL_OTHER_CFLAGS = -Wreserved-id-macro -Wdiv-by-zero -Wbad-function-cast  -Wnested-externs -Wold-style-definition
 
 // C++ Only Warnings
 GTM_GENERAL_OTHER_CPLUSPLUSFLAGS = -Wabi -Wctor-dtor-privacy -Wstrict-null-sentinel -Wsign-promo