Expose a single Clover Gadget via Bamboo

There are both advanced and very simple Clover gadgets written during ShipIt attack of the Gadgets, looking for a good server home.
see also: CLOV-561

This could be a quick win piece of low hanging fruit.

Lets start with the simplest form of Clover gadget: "Display the Red/Green Clover Coverage bar".
e.g.

This gadget will:

• pull the coverage data from a user specified Artifact (that is a Clover HTML report) from the latest Bamboo build for a specified Bamboo Plan
• render a red/green coverage bar showing the percentage of code coverage for a specific project
• display the raw total percentage figure
• support all gadget display sizes

If the Artifact points to the root directory of a Clover HTML report, then the gadget can assume there will be a 'project.js' available.
e.g. http://clover.atlassian.com/browse/webtest/project.js

If the Artifact points to a single .js file (presumably project.js), the gadget should just use it as the data source.

An example gadget (done during ShipIt 10) is available on Labs: http://labs.atlassian.com/browse/GOGO .
The sub-project 'clover' contains the gadget: http://labs.atlassian.com/svn/GOGO/trunk/src/clover/ .
This gadget is actually deployed and can be installed in any Open Social container. The URL is: http://labs.atlassian.com/gadgets/npellow/src/clover-gadget.xml

This gadget also uses the historical json to generate a visualization of coverage and project metric trends. This can be added to the gadget for a phase #2.