[SSSD] [PATCHES] Support IPA sudo schema

Hello list, the support of IPA sudo schema is almost complete. The only thing that remains is to finish smart refresh implementation and one patch to reduce code duplication between LDAP and IPA implementation. Then I need to run some tests but I don't expect much troubles here since I tested it a lot during development. I'll finish all of this after my Christmas vacation. The patches are probably too big to be sent as an attachment, so until I complete the last two patches, you can check it on my git repo, branch sudo [1]. I don't really expect anyone to review them during Christmas break, but I thought it's a good thing to present if in case someone will get really bored from all the candies and family visits :-) Happy reviewing. [1] https://fedorapeople.org/cgit/pbrezina/public_git/sssd.git/log/?h=sudo