Fixes bounty #324 - strengthen comment li selector specificity.
Remove nested p tags in comments.

Caused by nesting markdown inside p tag. See
https://assembly.com/coderwall/wips/324#comment-3.
Fix #307 - provide protip live preview.
Fix #288 - add provider user lookup.

- Add controller to pick up /providers/:provider/:username.
- Add service to look up user by provider.
Merge pull request #207 from carlwoodward/288-provider-user-lookup

Fix #288 - add provider user lookup.
Merge pull request #206 from carlwoodward/307-protip-preview

Fix #307 - provide protip live preview.
Merge pull request #204 from carlwoodward/324-styling-issues-in-comments

Styling issues in comments
Bumped gem
WIP#374 Handle unsubscribe requests and piggy-back off the old Weekly Digest settings
Merge pull request #208 from just3ws/master

WIP#374 Handle unsubscribes