Described custom validations
Merge pull request #206 from anatoliychakkaev/master

Documentation improvements
Eliminated global leak
Merge branch 'master' of github1602:1602/jugglingdb
Some cleanup of how generic relations work. Considering how to merge the other parts into this instead of keeping separate.
Merge branch 'bug-track'

* bug-track:
  Eliminated global leak
  Described custom validations