Fixed font application on Dark Theme

For some reason, Open Sans doesn't actually apply to user profiles when you're using the dark theme.
Removed hover behaviour

The column headers, as cool as they looked, get in the way of clicking on some things. Like people's names.
Returned hover behaviour

Should have done that on another branch. Oops.
Fixed grammar + added Firefox instructions
Merge pull request #4 from will1b/master

Fixed font application on Dark Theme