compare using epsilon and absolute difference
Added CCB_MEMBERVARIABLEASSIGNER_GLUE_WEAK

We've found it useful to use CCB_MEMBERVARIABLEASSIGNER_GLUE_WEAK in
situations where we don't want CCObject derived pointers retained. It's
also useful if you want to assign a pointer dynamically cast to an
abstract base class such as CCLabelProtocol.
Merge pull request #2402 from brawsome/master

fixed #2069: Adding new macro CCB_MEMBERVARIABLEASSIGNER_GLUE_WEAK to CCBMemberVariableAssigner.h
Update AUTHORS
fix a compiling error
Merge pull request #2404 from minggo/assetmanager

fix a compiling error
Merge pull request #2398 from lgb/float_comparison_issue

fixed #1935: Float comparison must not use "==" in the equal function of CCPoint and CCSize, we should compare float number by using epsilon and absolute difference.
Update AUTHORS
Removing unused file(uthash.h) in JSB projects.