Update README.md
Joined all the attribute readers.
Moved long assignment into smaller more readable lines.
Cleaned the long unreadable statement into smaller seperate lines.
Removed extra empty line at the body end.
Changed to Ruby 1.9+ hash syntax.
Avoid double negation.
Allow app to start w/o ERRBIT_EMAIL_FROM
Add Github_URL env var to Cloud66 configuration
Fix how to deploy to Heroku

`heroku labs:enable user-env-compile` is no longer available,
and the application on Heroku seems to works well without such configuration.
Merge pull request #718 from CodeForKids/master

Add Github_URL env var to Cloud66 configuration
Merge pull request #719 from tricknotes/fix-deploying-in-readme

Fix how to deploy to Heroku in README
use config.protocol instead of hardcoded http
Merge pull request #721 from manuelvanrijn/use-protocol-for-problem-url

Use config.protocol instead of hardcoded http
add test to ruby v2.1

since ruby head is 2.2dev is important keep that version here
Merge pull request #722 from lucianosousa/patch-1

add test to ruby v2.1
update rails version. add security pack
update another rails packages
Merge pull request #723 from lucianosousa/rails-3.2.19

update rails version. add security pack
Added Email Headers with lots of metadata

Added a shared_example to handle default specs for emails