All images format implementation but WIC test the value of a CC_USE_<FORMAT>
preprocessor macro to verify if the implementation must be available or not.
WIC support is checked against the definition of the macro only,
independently of its value, thus making the implementation available even
if CC_USE_WIC = 0.
This commit makes the tests of the CC_USE_WIC macro identical to the tests
of the other similar image format macros.
Move StringUtf8ToWideChar and StringWideCharToUtf8 to CCWinRTUtils(
Replace CCUtf8ToUnicode)
Use StringUtf8ToWideChar for convert utf8 to unicode
Use StringWideCharToUtf8 for convert unicode to utf8