in two halves to avoid integer overflows after 29 days.

except for POSIX timers case, which is currently the only natively absolute
timers implementation on LibVLC.

 - use utf8_(read|open)dir
 - do not assume that stat() succeeds (tiny race condition)

* added numerous casts to silence compilation warnings introduced with const chars in module_config_t. still needs severe testing on other Macs.

Might break stuff, but I cannot test much because of DBus vs Win32 breakage(!)

  if !defined _WIN32 should be either ifndef _WIN32 or if !defined(_WIN32)

- and merge some ASM/SSM code

* destroy some mutex'es once in a while to prevent memleaks. Suggested by a forumuser, name pending.