Prepare for ICU update

- libicule and libiculx do not exist anymore in newer ICU versions
(harfbuzz replaces them), but we didn't actually use them, so remove
them from the build feature and from the package dependencies
- Add namespace usage marcos since the newer ICU packages put ICU things
in a namespace, making it easier to have multiple versions of ICU used
side by side.

No functional change intended, but this makes it possible to build the
code with either ICU 57 (for gcc2) or 66 (for other architectures).

include strings.h where appriopriate...

instead or additionally to string.h, in preparation for functions move.
* moves str[n]casecmp() functions and others to strings.h.
* strings.h doesn't include string.h anymore.
* this solves #10949

Allow switching of timezone string to messages locale, too.

* adjust POSIX locale backend to redirect the timezone string
through the messages/time-locale indirection

Implement taking date strings from messages locale.

* mimic LocaleKit and add option to POSIX locale backend for taking
the date strings from the messages locale (instead of time locale)

Bring rewritten multibyte-support into repository.

* update copyrights of locale backend files

Multibyte-support has been rewritten to use ICU as backend.
While this does not necessarily work properly in every aspect
(e.g. the shell still has [different] problems with multibyte-
characters now), it does fix #6263 and #7700.

Use TLS and converter manager in locale backend.

* Merged weak-symbols branch.
* Fixed trivial merge conflict in src/system/libroot/posix/locale/nl_langinfo.cpp
* Fixed gcc 2 compilation of src/system/glue/init_term_dyn.c.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39571 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement tzset(), gmtime(), localtime() and mktime() on top of ICU
* no longer keep a separate time-backend, since the implementation needs to
access (data of) the locale backend anyway
* moved more stuff from localtime_fading_out.c to localtime.cpp
* added respective tests to locale_test
* added two more tests copied from glibc, test_time.c and tst-mktime.c


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38162 a95241bf-73f2-0310-859d-f6bbb57e9c96

include strings.h where appriopriate...

instead or additionally to string.h, in preparation for functions move.
* moves str[n]casecmp() functions and others to strings.h.
* strings.h doesn't include string.h anymore.
* this solves #10949

Allow switching of timezone string to messages locale, too.

* adjust POSIX locale backend to redirect the timezone string
through the messages/time-locale indirection

Implement taking date strings from messages locale.

* mimic LocaleKit and add option to POSIX locale backend for taking
the date strings from the messages locale (instead of time locale)

Bring rewritten multibyte-support into repository.

* update copyrights of locale backend files

Multibyte-support has been rewritten to use ICU as backend.
While this does not necessarily work properly in every aspect
(e.g. the shell still has [different] problems with multibyte-
characters now), it does fix #6263 and #7700.

Use TLS and converter manager in locale backend.

* Merged weak-symbols branch.
* Fixed trivial merge conflict in src/system/libroot/posix/locale/nl_langinfo.cpp
* Fixed gcc 2 compilation of src/system/glue/init_term_dyn.c.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39571 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement tzset(), gmtime(), localtime() and mktime() on top of ICU
* no longer keep a separate time-backend, since the implementation needs to
access (data of) the locale backend anyway
* moved more stuff from localtime_fading_out.c to localtime.cpp
* added respective tests to locale_test
* added two more tests copied from glibc, test_time.c and tst-mktime.c


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38162 a95241bf-73f2-0310-859d-f6bbb57e9c96