moodlelib: Introducing the cache_flags functions
moodlelib: Introducing the cache_flags functions

These are functions for handling the volatile entries in the
cache_flags table.

 get_cache_flags() - get array of current flags
 set_cache_flag()  - set a single flag
 unset_cache_flag() - unset a single flag
 gc_cache_flags() - garbage-collect expired flags

dilawar/moodle