Removed several useless macros: UNISTRING, USTR, USTR_ASCII, ASCII_STR, ASCII_STRING, CONST_ASCII, ASCSTR, ASCII, DEFINE_CONST_UNICODE, DEFINE_CONST_OUSTRING

Change-Id: I96d690bf9f9b319e9eeafcf218ec5ce87f21215f
Reviewed-on: https://gerrit.libreoffice.org/1954Reviewed-by: Tor Lillqvist <tml@iki.fi>
Tested-by: Tor Lillqvist <tml@iki.fi>