Update MANIFEST and setup.py to use README.rst
Hide database errors when setting the search path

It's needed to allow ROLLBACK to be executed on the DB. It resolves
issue #191.
Use warning to complain about tenant_schemas place in INSTALLED_APPS
Merge pull request #190 from rev112/update_manifest_readme

Update MANIFEST and setup.py to use README.rst
Merge pull request #195 from bdauvergne/wip/remove-useless-warning

Use warning to complain about tenant_schemas place in INSTALLED_APPS
Merge pull request #193 from bdauvergne/wip/fix-database-transaction-errors

Hide database errors when setting the search path
Django 1.7 support

    * `migrate` now automatically calls `migrate_schemas` if django version >= 1.7; This is important as many parts of django (like test suit) calls django's migrate command to sync tables. The whole ecosystem now assumes that `migrate` command is available and some libraries migh try to automate calling it. Making it fail instead of properly synching tables to right schemas breaks automation.