Author: Laurent David
MDL-77545 mod_bigbluebuttonbn: Add form extension
* Add a new way to extend the BigBlueButtonBN form via subplugins
* Allow subplugins to extends information via new tables and use it in
the edit form.
* Add a new cache helping with potential perfomance issues introduced
by recurring calls to find out about associated tables in subplugins.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=0335adeff42da62f72b26abfcf16a18ec54e9ca5
http://github.com/moodle/moodle/commit/0335adeff42da62f72b26abfcf16a18ec54e9ca5
+ 4.3 en [cachedef_subplugins,mod_bigbluebuttonbn]