chore(core): increase timeout for testing

Increase timeout for integration testing to 20seconds for setting
up the server, because Travis can be slow.
chore(core): increase timeout time for test again

Increase timeout for integration tests from 20s to 40s because
Travis is quite slow.
choir(core): increase again timeout for tests
choir(core): add Plumber to handle Gulp errors
choir(core): remove Plumber from test suites

Remove Gulp plugin Plumber from test hook because it makes failing
test not actually fail.
chore(core): remove silent mode from Sails

Remove silent mode from Sails in integration tests, to print
useful messages when something goes wrong.
chore(core): try to fix Travis RDS connection

Tries to fix Travis accessing securely RDS credentials to do
tests while using AWS database.
chore(core): try to fix Travis database problem
chore(core): try to fix Travis database again
chore(core): remove stub testing RDS connection
chore(core): Fix RDS connection problem
chore(core): add PostgreSQL connection tests
chore(core): add debug messages for database test
chore(core): remove Travis env. var
chore(core): add env. var back to Travis
chore(core): fix sails.lower() called twice
chore(core): update RDS database password
choir(core): only deploy once per push with Travis
chore(core): fix up test coverage
chore(core): fix final test callback called twice