Add mining yield view

Add a panel for displaying the mining yield. Display miner and drone
yield. Only create the frontend in this commit.
Calculate mining yields for module/drone

Following the weaponStats paradigm, add mining yield information
throughout the drone/module modules
Use a button to toggle between firepower/miningyield

Introduce a button on both firepowerViewFull and miningyieldViewFull
views that allows switching between the two. Work by destroying each
view and recreating/populating on every button press.
Use small icon with mining yield / firepower toggle button
Merge branch 'akosiaris_miningyeild'