Added Traderable interface to Transactions.
Players can now trade with Traders encountered in space.
Merge branch 'master' into sam/dev.

Conflicts:
	src/main/java/edu/gatech/gem5/game/controllers/DisplayUniverseController.java
	src/main/java/edu/gatech/gem5/game/controllers/EncounterController.java
last commit before pull from master.
Merge branch 'master' of https://github.com/gem-5/last-adventures into sam/dev
Traders now spawn with inventory goods that they can trade to the player.
Fixed UI bug, where trading with Trader was labelled as Planet.
Added trader.fxml file for TraderController
Bigger and better universes are here! Enjoy full panning and zooming action with incredible life-like immersion!
Some enhancements to the new universe display.
Started implementing random events, but there is no chance that it will occur yet, because no event screen exists.
Merge branch 'master' into jack/dev
Major style update. Also added new star types to solar systems - update your save files!
Created ShipyardController, edited UpgradeBar so that ships can be sold.
Merge master into alex/dev

Conflicts:
	src/main/java/edu/gatech/gem5/game/controllers/PlanetController.java
Added radio buttons to the ship yard. Ship yard labels now update on upgrade.
Redid the data manager. It is now a class called Data, and everything in it is static. Reduces the amount of code and any casting used previously.
Merge with myself from master to jack/dev
Forgot to get rid of other branches' stuff on the merge
Begin recovery of all my files :(