I discovered while trying to use UserTeam#remove_member() that
UsersProject.in_projects was broken.  So I wrote test cases to test what
I was trying to do and fixed the underlying problem.

Spork support added

Better header and detail why you need two times the storage. Also moving memory and storage to the bottom, OS is more important.

bump version of grit_ext

Fixing a minor typo in the installation docs

Update databases.md