Update some minicore menus

* Adds slot checked/selected gfx
* Adds gold icon
* Updates various widget positions in config/inventory/actionbar menus
Merge pull request #327 from dorkster/fixes

Update some minicore menus
Add desktop file and svg icon
Merge pull request #330 from dorkster/fixes

Add desktop file and svg icon
Added simple setup steps
Add detailed Linux build/install instructions to README
Change "Installation" to "Building and Running" in README

The instructionsaren't limited to system-wide installation.
Merge pull request #333 from dorkster/docs

Add detailed Linux build/install instructions to README