Deprecate getSavesDirectory as the name is wrong. Add getGameDirectory as that is what it actually is.
Deprecate getSavesDirectory as the name is wrong. Add getGameDirectory as
that is what it actually is.

Signed-off-by: Chris Sanders <becb1b07b5e7418402924748493938777e4ce438@spongepowered.org>

AlphaModder/SpongeAPI,SpongePowered/SpongeAPI,SpongePowered/SpongeAPI,JBYoshi/SpongeAPI,AlphaModder/SpongeAPI,SpongePowered/SpongeAPI,JBYoshi/SpongeAPI