Create FreeTypeFontLoader and FreeTypeFontParameters

Having a type that extends AssetLoaderParameters is necessary in order
to pass parameters to the font generator. This type is
FreeTypeFontParameters.

FreeTypeFontParameters simply contains a public FreeTypeFontParameter
because there is not a way to extend both FreeTypeFontParameter and
AssetLoaderParameters. Neither are interfaces.

Color and scale are not set within the loader, because these can be set
on a BitmapFont after it has been generated. The opposite is true for
anything that goes in a FreeTypeFontParameter.
Wire up FreeTypeFontLoader with AssetManagerPlus and load a font
Use loaded font in LevelScreen
Set color and scale when rendering, not when the font is retrieved

The same bitmap font may be used in multiple places, and each place may
want to render it a different color and size. This is the case with
LevelScreen and LevelTitleScreen.
Get title font from assets

It is done in show because the font isn't loaded yet when
LevelTitleScreens are being constructed

[Regression]
LevelTitleScreen font scale is way off
Fix font sizing, but now there are scaling issues
Create BitmapFontGroup

This will be the new class that the assetloader will be set to load when
using freetypefontloader.

It's not possible to do Map<String, HashMap>.class, so the workaround is
to just make a specialized type that extends Map<String, HashMap>, and
use .class on that.
Update FreeTypeFontParameters so that it works with BitmapFontGroup

Previously, FreeTypeFontParameters only held a single
FreeTypeFontParameter object. We are working towards having a
FreeTypeFontLoader that can load multiple BitmapFonts from a single
FreeTypeFont, so FreeTypeFontParameters needs to be able to hold
multiple sets of parameters.

The name that is associated with any FreeTypeFontParameter will be the
name that is used to get the BitmapFont that is created from that
FreeTypeFontParameter from its BitmapFontGroup.
Update FreeTypeFontLoader to use BitmapFontGroups
Update usage of the new asset loader for BitmapFontGroups

The method makeCorbelParams() should be an adequate example of how to
load fonts with the new loader, and an example of how to get the font
that is created can be seen in either LevelScreen or LevelTitleScreen,
in setupFonts() or generateFonts() respectively.
Rename class to better reflect its purpose
Merge pull request #40 from SweatyReptile/fontloader

Load fonts using FreeTypeFontLoader (AssetManager)