Add clickability/tooltip to profile badges

[marktimemedia]

The WordPress.org profile badges are awesome, but would be more useful if they had:

a) a tooltip saying what they meant (in case people viewing the profile don't know what the icons stand for), and

b) clickability to take you to a destination, either the main "make" site or to a single central page that details all of the different badges.

[marktimemedia]

Duplicate of #527.

[iandunn]

Adding text to them is being discussed in #420.