Workaround another race condition issue

See https://bugzilla.redhat.com/show_bug.cgi?id=921706
[ko.orth] Remove U+3164 HANGUL FILLER

Better not to reject a font just over that.  Note that we do NOT
list U+115F and U+1160 either.
Deprecate FC_HASH and don't compute it

It was added without proper measurement and a fuzzy possible
use-case (font servers) in mind, but reality check shows that
this significantly slows down caching.  As such, deprecate it
and do NOT compute hash during caching.

Makes caching two to three times faster (ignoring the 2 second
delay in fc-cache).
Remove unused FcHash code now that FC_HASH is deprecated
Read the config files and fonts on the sysroot when --sysroot is given to fc-cache

Fix for e96d7760886a3781a46b3271c76af99e15cb0146

https://bugs.freedesktop.org/show_bug.cgi?id=59456
Update list of blanks to Unicode 6.3.0

Some were bogus, some were missing.  See:

  https://bugs.freedesktop.org/show_bug.cgi?id=79956
Fix a segfault

introduced by the previous commit d17f556153fbaf8fe57fdb4fc1f0efa4313f0ecf
Update CaseFolding.txt to Unicode 7.0
Update blanks to Unicode 7.0
Don't read/write from/to the XDG dirs if the home directory is disabled
Rework for 5004e8e01f5de30ad01904e57ea0eda006ab3a0c

Don't read/write from/to the XDG dirs even if XDG_*_HOME is set
and the home directory is disabled.
Change charset parse/unparse format to be human readable

Previous format was unusable.  New format is ranges of hex values.
To choose space character and Latin capital letters for example:

$ fc-pattern ':charset=20 41-5a'
Pattern has 1 elts (size 16)
	charset:
	0000: 00000000 00000001 07fffffe 00000000 00000000 00000000 00000000 00000000
(s)
Minor
Fix charset unparse after recent changes
Fix a crash when no sysroot is given and failed to load the default fonts.conf
Comments
Remove HASH from matching priorities

We deprecated FC_HASH, so doesn't make sense to sort on it.
Fixup previous commit
Fix a gcc warning

test-migration.c:17:5: warning: pointer targets in passing argument 1 of 'FcStrDirname' differ in signedness
Update mingw32 MemoryBarrier from HarfBuzz

Fixes https://bugs.freedesktop.org/show_bug.cgi?id=81228