Add outline for PostgreSQL schema support, PostgreSQL-specific tests
Add schema resolution to PostgreSQL operations

Also fill out test cases for PostgreSQL-specific tests.
Skip PostgreSQL-specific tests on Sqlite
Fix crash on bad schema searching, bad user schema resolution
Add search path args to tracking setup/teardown methods
Fix crash with default empty options
Merge branch 'postgresql_schemas'

Add support for multiple, non-default schemas for PostgreSQL
Merge branch 'master' into gemify

Conflicts:
	Rakefile
	adapters/postgresql.rb
	db.rb
	lib/data_task/adapters/greenplum.rb
	lib/data_task/adapters/sqlite.rb