Merge pull request #73 from lob/fix-area-tests

chore(fix-tests): fixes failing area tests
lob-ruby should not callout to rubygems to get the version number. The gem should know it's own version number through a version file.
Merge pull request #75 from lob/version-module

Version module addition
chore(error-messaging): better error handling and message
Merge pull request #76 from lob/better-error-handling

chore(error-messaging): better error handling and message
chore(api-version): adds support for api versioning