Remove schematic submodule

If you're using schematic, you need to:

1. install schematic into vendor-local

2. remove the now unmaintained, unversioned vendor/src/schematic/ directory

3. update the deploy code to use the correct schematic path

4. update your documentation regarding running migrations because
   schematic is in a new place
Merge pull request #53 from willkg/remove-schematic-2

Remove schematic submodule