* grp.cc (get_groups): New static function to run the core functionality
of initgroups and getgrouplist.
(initgroups32): Call get_groups and just create supplementary group
list in cygheap. Rename name of first argument to "user". Add an
assertion to test for a NULL user name.
(initgroups): Rename name of first argument to "user".
(getgrouplist): New function.
* posix.sgml (std-bsd): Add getgrouplist.
* include/cygwin/grp.h (getgrouplist): Declare.
* include/cygwin/version.h: Bump API minor number.