move seed data from the migrations to the default data loader. also enhance the seed task with the loading default data task.
let's use data_already_loaded? instead of no_data? (no_data? is kept around in case some plugin depends on it)
sync up the migration based schema.rbs of mysql and postgres.

* check in the schema.rb file (postgres as reference, no duplicate indices)
* added a migration which syncs up the schema.rbs between postgres and mysql. doing a full migration on both databases now exactly produces the same schema.rb. therefore we can run rake db:setup (schema load + seed data) instead of all migrations, just as rails wants us to.
fixes minimum password length requirement
fix for circular dependency bug