Add blacklist functionality
Add HEAD request for imaging
Merge pull request #342 from justinribeiro/add-HEAD-req

Add HEAD request for imaging
Update thumbor-worker Upstart job

Removed enabled=1 check, as you can just use `update-rc.d enable|disable` for that purpose (or add `exit 0` to the default file). Changed instance variable to be more meaningful. Removed bad usage of /tmp (it was unsafe and allowed escalation to root).
Updated thumbor upstart job

Removed check of enabled=1 (see previous commit), renamed port var to ports, adjusted start/stop events slightly.
Changed port to PORT, since default files will override the variable
ports went back to port, so default files do not break
Merge pull request #339 from voxmedia/blacklist

Add blacklist functionality
Add http loader configuration keys for cacerts and client ssl
Fix #346. Support for optimizers. Included jpegtran as example implementation.
Release 4.5.0
Fixing to only process jpeg files
Release 4.5.1
Removing jpegtran as the default optimizer
release 4.5.2
Fixing issue with file not being closed before being read by jpegtran
release 4.5.3
Remove pdb
Merge pull request #361 from mattrobenolt/pdb

Remove pdb
sentry_error_handler_vows: Fix 'Sentr' -> 'Sentry' typo

This dates back to the creation of this vow in 44c432d2 (Error handler
vows. 100% covered now, 2013-03-28).