Fix compile errors, code review feedback, and add basic libc test suite.

*** 97,103 ****
--- 97,104 ----
  extern struct locdata   __posix_monetary_locdata;
  extern struct locdata   __posix_messages_locdata;
  extern struct locdata   __posix_time_locdata;
  extern struct locdata   __posix_ctype_locdata;
  extern struct locdata   __posix_collate_locdata;
+ extern locale_t ___global_locale; 
  
  #endif  /* _LOCALEIMPL_H_ */