warrior ui: Adds "help & about" tab

Closes ArchiveTeam/seesaw-kit#38
Warrior UI: Rename "Help & about" to just "About"

The tab label looks a bit off since the existing tabs are not title
cased.
Warrior UI: Increase the about tab content font size
Merge pull request #58 from chfoo/issue/38-help-tab

Warrior UI: Adds a "Help & about" tab