Adds Lua include path to fix XCode build error in new project.

gameplay-template/gameplay-template.xcodeproj/project.pbxproj

@@ -434,6 +434,7 @@
 					"GAMEPLAY_PATH/external-deps/libpng/include",
 					"GAMEPLAY_PATH/external-deps/bullet/include",
 					"GAMEPLAY_PATH/external-deps/oggvorbis/include",
+					"GAMEPLAY_PATH/external-deps/lua/include",
 				);
 				INFOPLIST_FILE = "TEMPLATE_PROJECT-macosx.plist";
 				LIBRARY_SEARCH_PATHS = (
@@ -460,6 +461,7 @@
 					"GAMEPLAY_PATH/external-deps/libpng/include",
 					"GAMEPLAY_PATH/external-deps/bullet/include",
 					"GAMEPLAY_PATH/external-deps/oggvorbis/include",
+					"GAMEPLAY_PATH/external-deps/lua/include",
 				);
 				INFOPLIST_FILE = "TEMPLATE_PROJECT-macosx.plist";
 				LIBRARY_SEARCH_PATHS = (
@@ -487,6 +489,7 @@
 					"GAMEPLAY_PATH/external-deps/libpng/include",
 					"GAMEPLAY_PATH/external-deps/bullet/include",
 					"GAMEPLAY_PATH/external-deps/oggvorbis/include",
+					"GAMEPLAY_PATH/external-deps/lua/include",
 				);
 				INFOPLIST_FILE = "TEMPLATE_PROJECT-ios.plist";
                 IPHONEOS_DEPLOYMENT_TARGET = 5.1;
@@ -516,6 +519,7 @@
 					"GAMEPLAY_PATH/external-deps/libpng/include",
 					"GAMEPLAY_PATH/external-deps/bullet/include",
 					"GAMEPLAY_PATH/external-deps/oggvorbis/include",
+					"GAMEPLAY_PATH/external-deps/lua/include",
 				);
 				INFOPLIST_FILE = "TEMPLATE_PROJECT-ios.plist";
                 IPHONEOS_DEPLOYMENT_TARGET = 5.1;