setting default user agent to 'RethinkDB'
adding default r.http auth type as 'basic'
adding new r.http tests
merging larkost/2390-remove-proto-buffers

Issue #2390 Remove the need for the proto-buffers ruby gem
Bypass the need to have the ruby proto-buffers gem installed in order to translate the master proto buffers file into a ruby hierarchy
Merging #1565 Provide a signed OS X package

Add the flag to productbuild to sign the resulting .pkg/.dmg, and the conditional code to make sure it only comes into play when available/required. In addition to this code the required certificate and private key need to be in a keychain on the signing system and visible to the signing process.
changing to older name for curl option define
changing user agent setting to be more robust and allow for user agent spoofing
Merge branch 'next' into sam_2353