* On specific platforms (it seems Windows 7-10, JRT 7+), under our specific configuration, in the case where the user selects the exact same file as they chose during a previous selection, JFileChooser reports that the user selected a file, but returns chosen file = null. This commit works around that by assuming they chose the same file as last time in that case.
* Working standalone proof-of-concept application in DragCardGrid.
* Still needs listener functionality in order to integrate it into the existing DeckEditorPanel class.
* Rather than respecting the spacing setting from Preferences, the spacing is now calculated from the card size if characteristic based rendering is enabled, since from the renderer we know exactly what spacing is actually needed.
* Simply invalidating the image render is not enough, a repaint call is also needed in a few cases where a repaint hadn't already been scheduled by the same change that trigged the selectable/chosen status change.
* Turns out that drawing black borders on non-rendered cards, while it fixes what was probably a bug, has unintentional and undesirable implications. Needs further work in the future, but revert it for now.
* Basic lands have the mana symbol in their textbox rather than their actual text. That was erroneously being applied to other permanents like Elvish Mystics with only a single mana adding ability as text.
* Deck area orientation now changes depending on the context.
* In free building and sideboarding, the sideboard and maindeck are shown side by side.
* In limited deckbuilding, the sideboard (with your limited pool) is shown above the maindeck.
* Vehicles are rendered with a vehicle background and changed P/T box color
* Kaladesh Inventions are rendered with the invention frame
* Kaladesh Inventions use the full-frame art if they detect that you have that full art downloaded instead of normal card images.
* Changed land text-box colors to be a bit more saturated to make it clearer what colors they produce
* Added mana symbol in the textbox of basic lands instead of rules text as long as they have no additional abilities.
* Fixed problem with triggered abilities on the stack showing up with a type of "??? Ability". Not sure what the real cause is but those abilities have abilityType = null, just worked around it.
