* Grit gem updated
* gitolite-client updated
* logger added
* few fixes

Use modified pygments.rb to allow dependency to rubypython 0.6.1 or above that fixes installation issues on some 64bit OSes like RHEL-based Scientific Linux 6.

Covers new user, new issue and wall note emails.

Depends on email_spec (https://github.com/bmabey/email-spec/) for
friendly matchers.

Pinned devise to the 1.x series for the moment. Going to 2.0 threw
deprecation warnings about:
* Devise.stateless_token= (append :token_auth to Devise.skip_session_storage instead)
* devise.registrations.reasons in yml (use devise.registrations.signed_up_but_REASON)

This gives us Github Flavored Markdown, which is awesome.

This reverts commit a25a85b9.

This commit includes:

 * Projects can have zero or more WebHooks.
 * The PostReceive job will ask a project to execute any web hooks defined for that project.
 * WebHook has a URL, we post Github-compatible JSON to that URL.
 * Failure to execute a WebHook will be silently ignored.