Pmail 20141107 rc

Second pass at pmail exercise, includes revisions based on @ashtonthomas feedback

Updated live example can be found here: http://cowanryan.com/pmail/

-add `cursor: pointer` to various items
-add minor spacing to pagination content (ex: 1 - 12 of 12)
-two emails now show as "unread" with appropriate styling
-refactor view of mail menu and mail content, now use fixed width for mail menu while the mail content extends to page width
-drop "pure" prefix on custom button styling
-scale back use of `ID`s to just items used by JavaScript

Initial changes can be found in PR #255 
See below about semantic class naming. You can't require it for those `pure-*` classes, but at least your classnames should be semantic.