first pass flxemitter refactor
more refactoring
FlxEmitter refactor: compiler errors fixed
FlxEmitter refactor: fix null errors due to uninstantiated vars
FlxEmitter refactor: removed distance, use lifespan instead
FlxEmitter refactor: Fix bugs, add makeParticles
FlxEmitter refactoring: see PR comments
FlxEmitter refactor: changes per @gama11, add FloatRange class
FlxEmitter refactor: improvements and bug fixes
FlxParticle refactor: small tweaks
fix merge conflict with flxparticleext
FlxEmitter refactor: don't override calculated velocity changes
FlxEmitter refactor: helper classes all use set(), minor bug fixes and improvements
update changelog
FlxEmitter refactor: fix x/y/width/height calculation
FlxEmitter refactor: fix typo in flxpointrangebounds
FlxEmitter refactor: use _point for launch velocity calculations
FlxEmitter refactor: default particle scale and alpha now 1, do not kill() if lifespan = 0
FlxEmitter refactor: changes per @gamedevsam
flxemitter refactor: fix conflict between flxpoint and flxemitter