Workaround for runantlr not setting up date stamps.

That forced antlr to run every time. The workaround is to remove the output directory
so files are generated from clean slate, thus have proper time stamps.

libwccl/CMakeLists.txt

@@ -80,6 +80,7 @@ ADD_CUSTOM_COMMAND(
 		${PROJECT_BINARY_DIR}/parser/ANTLRParser.hpp
 		${PROJECT_BINARY_DIR}/parser/ANTLRExprTokenTypes.hpp
 		${PROJECT_BINARY_DIR}/parser/ANTLRExprTokenTypes.txt
+	COMMAND ${CMAKE_COMMAND} -E remove_directory ${PROJECT_BINARY_DIR}/parser
 	COMMAND runantlr -o parser ${PROJECT_SOURCE_DIR}/parser/grammar.g
 	DEPENDS ${PROJECT_SOURCE_DIR}/parser/grammar.g
 	COMMENT "-- Generating ANTLR parser cpp/hpp/txt files")