This patch implements posix_openpt() and ptsname()
grantpt() and unlockpt() are left in LibC as stubs, as posix_openpt
currently does all of the needed work.
This patch adds 2 locales, POSIX locale and UTF8 locale.
functions `mbstowcs()` and `strcoll()` use locales to do convertions and
comparison respectively.
realpath is implemented as a syscall. This is not really required but it
was the easiest way to get it working as there is already path
canonicalization at kernel level.
Bananymous