Added invite-only projects.
Merge pull request #291 from pleary/paths

Enabled garbage collection profiling; saving more COUNT() queries; faste...
Merge pull request #279 from inaturalist/inviteonly

Added invite-only projects (Issue #75)
Bugfix: taxon change form wasn't adjusting field order correctly.
Minor spec fixes.
Type check for marshal_copy.
Added array to that check.
Minor fixes for invite-only projects.