PkgConfig use 'separate_arguments' for pkgconfig result, so output
converted to the list (in cmake it's semicolumnt separated values).
If we try to append CFLAGS_OTHER as is, it will provide error for
more then one cflag in '.pc' file
Fix#4175, fix#4457.
Scripts updating versions in source depend on GNU sed which is sometimes
not set as the default on some OSes.
With the change, one will need to manually call the update script before
releases.
Fixes#4439.
One part fixes#4280 (removing this flag giving qTox on Windows able to start properly), another part fixes my mistake in #4258 (strmiids still needed for
linking, but previous searching of this libstrmiids.a wasn't include, for example, '/mingw32/i686-w64-mingw32/lib'. So I just add this lib to $ALL_LIBRARIES,
because it exists in system by default).
Fixes bulding with cmake on Windows. strmiids is exists as a
libstrmiids.a static library, but cmake can't find it. Because of
useless of this search and successful building without it, I'm removed it.