cleaner backtrace in specs
add test that page query param will be overriden
prevent tampering with host, port, protocol

Prevents :host, :port, :protocol settings get inherited from GET query
parameters.

Fixes #285
Fix `script/test_all` to exit with nonzero status on failures

Fixes #387
Ruby 2.1.1 compat for tests
Bump Rails in tests to 4.0.5
Ignore `SHOW FULL FIELDS` in tests
Test with Ruby 2.1.2 but not with 1.9.2