Unified key/joystick bindings & mouse emulation

These two features ended up going together. The MAIN1 key needs to behave
differently based on its context (combat vs menus). Mouse emulation gives a
way to handle both of these contexts. Basically, mouse emulation is turned
on when in menus and off when in combat. All of this combined means that
Flare is now be played entirely with a joystick.

In addition, GameState* menu keyboard shortcuts have been removed. There
were conflicts with mouse emulation and these shortcuts. Not to mention
the amount of menu navigation with these keys was limited (couldn't operate
the Configuration menu) and made the code messy. By having only the mouse
cursor (emulated or otherwise) operate on widgets, we keep things
consistent.

Finally, a bug in GameStateConfig where joysticks could be enabled without
picking a joystick from the list was fixed.

Known issues:
* The mouse can still be used when in mouse emulation mode. However, the
cursor is hidden and placed in the bottom-right to prevent it from
interfering with combat. I didn't want to lock the mouse in that corner
because it's not good for people that play in windowed mode. This is the
best compromise for this that I could come up with.
Don't hide cursor when mouse emulation is off
Fix elemental resists/weaknesses for enemies

By having a vulnerable_base stat, the vulnerable_* values given in enemy
definition files won't be overwritten when effect bonuses are applied.
Fix Avatar transform stat maxes
LootManager: Remove unused function lootLevel(int base_level);
WidgetLabel: remove unused function setValign(int _valign);
WidgetLabel: remove unused function setColor(SDL_Color _color);
Merge pull request #349 from makrohn/fixTransformDamage

Fix Avatar transform stat maxes
Merge pull request #351 from stefanbeller/master

Remove unused functions.
Merge pull request #345 from dorkster/joystick

Unified key/joystick bindings & mouse emulation
Merge pull request #346 from dorkster/bugfixes

Fix elemental resists/weaknesses for enemies
Merge pull request #348 from dorkster/transform

Fix transform bugs