replace mysql2 gem with pg gem
schema.rb changes for postgres
replace mysql-specific quoting syntax with db-agnostic quoting

tests are now fixed
may as well quote consistently
adapt entity values index and usage for postgres
refactor goofiness into a scope
fix value queries with more than 50 characters
typo fix
remove unnecessary association
begin using our acts_as_sane_tree fork
remove unnecessary line
remove commented out code
Fix travis build
this case is only valid for root entities
simplify a tad