Plugin installer packages

[moonscapex]

It is a real pain having to patch every plugin you want to install, and half of them do not work.  It would be nice if you could install plugins, like you can on Ubuntu, by just clicking on them.

[Llorean]

The appropriate solution is actually to figure out why the plugin isn't already included, and fix these problems.

[saratoga]

This will not happen.

[soap]

This will not happen because plugins are not apps, and must be built from the same SVN revision as the core of Rockbox, making binary distribution in any manner outside the current method near worthless.

_{Which is why the Ubuntu analogy fails.}
^{Simplification, but true enough.}