Show attribution on pastes

Displays the email address of the paster and a timestamp under the
paste contents. This change is backwards compatible with existing
datastores and memcache instances that lack attribution metadata.
Merge pull request #7 from maginatics/attribution

Show attribution on pastes
Add an optional title to pastes

Displays in title as well as first element in the body.
Merge pull request #4 from maginatics/title

Add an optional title to pastes
Unicode safe encoding for template params.
Gaestebin 2.0

- Go backend
- AngularJS frontend
- Bootstrap 3.1