Improve MacroStandardFindModule

Add 3 new arguments
* NOT_REQUIRED: Do not fail if pkg-config was found but it cannot find
                the package. Necessary if you want to try to find the
                package using some custom search.
* SKIP_CMAKE_CONFIG: Skip the check for the CMake Config file
* SKIP_PKG_CONFIG: Skip the check for pkg-config
Use the new MacroStandardFindModule flags in FindACE

Should fix searching for ACE on windows if pkg-config is installed.