add_user takes a user dictionary now, not a string.

* Fix old variable references

* Fix calling functions
Make an ughs module, move server.py there.
validate_user takes a user dictionary, not a string.
fix bare word userid key (changed to "userid")
Initial testing check in.
show_user only takes a userid
Fix errors with user / group modification

* Make sure group changes are applied to users previously in that group / now added

* Make sure user changes remove / add users to groups appropriately

* Fix bug in user modification function
s/user_id/userid/
Fix bugs with user deletion

* issue in storage backend with group cleanup

* issues in delete_user function
More tests!
Fix bug with get_users_for_group
More tests!
whitespace cleanup
pep8
whitespace and shebang
pep8
use new_user instead of copy
Fix delete user
Add test for deleting a nonexistent group