Improvements in Label

- Refactored Label::createFontChars()
- Renamed setHorizontalPadding() to setLetterSpacing()
- New test: Spacing
Renamed FZ_LIST_FOREACH_SAFE() to FZ_LIST_FOREACH_MUTABLE()
fzHash is an unsigned 32bits integer.
Some AutoList's methods are const.
Renamed FZ_SAFE_APPLY_MATRIX() to FZ_PROGRAM_APPLY_TRANSFORM()
Compile-time hash function. Part 1.
Compile-time hash function. Part 2.
Removed deprecated code in Filter.

The quality property is not part of the Filter's logic.
Cosmetic changes.

- More consistent
- Comments
- Indentation
New method in Node. countAllChildren()

countAllChildren() counts the number of children recursivelly.
Refactored FNT parser:

- Flexible
- Unlimited lines
- Memory efficient
- Fast
Removed unused code. setContentSize() in SpriteBatch
Last changes before v0.1rc2