Re-implement save & load methods

* All JSON keys are in lowercase format now (eg. ID is now id)
Fix indention & make JSON keys all lowercase
Sublime Project Settings: clean up ignored files

* Remove: ttcards.app, ttcards.dSYM, public -- these are all in build
dir now (ignored already)

* Ignore: third-party dir
Card: Introduce LEVEL_MIN & rename MAX_LEVEL

* MAX_LEVEL -> LEVEL_MAX
Fix several MSVCPP type compile warnings

* This also corrects an off-by-one error that occurs on Windows when we
are randomizing our player's hand (see line +221 of src/CardHand.cpp)
Windows platform: Fix bug upon switching from FS
Allow player to randomize card selection

* Remove DEBUG preprocessor check