CRM-15578 - crmMailing2 - Cleanup logging. Improve backtraces.
CRM-15578 - Mailing API - Fix SQL escaping

Note: The offending code only exists in a feature branch -- it was never
merged into mainline.
CiviUnitTestCase - Add helper useTransaction()
CRM-15578 - Mailing API - Add unit-test for send_test with group ID
CRM-15578 - api_v3_MailingTest - Prettify

Now that this test class calls useTransaction(), it's not necessary to
garbage-collect specific records by ID, so there's no need to maintain an ID
list.
CRM-15578 - api_v3_MailingTest - Make testMailerSendTest_email more robust
CRM-15578 - crmMailing2 - Implement "Send test" buttons
CRM-15578 - crmMailing2 - Tweak "Preview" status notification
crmMailing2 - Tweak syntax
CRM-15578 - crmMailing2 - Set default test email address to current user
CRM-15578 - Mailing.create - Fix updates to "groups" and "mailings". Add test.
CRM-15578 - crmMailing2 - Fix loading of recipient-group IDs
CRM-15578 - crmMailing2 - When ID of new mailing is established, update navbar.
Merge pull request #4596 from totten/master-civimail-sendtest

[DNM] CRM-15578 - CiviMail - Cleanup/implement support for sending test msgs