keep super class constructors if child constructor is explicitly kept (closes #2121)
Don't check for undefined window in js.Browser (browsers have windows)
Fix typo in JqEvent#isPropagationStopped

Fixes spelling and aligns JqEvent method name with jQuery event object method name.
do not unify cast return types, check for equality instead (closes #2125)
keep type stack to avoid infinite recursion while DCEing (closes #2124)
inlined Std.is for class/interfaces (x40 speedup)
make sure we keep the specific iterator type for inlining purposes
Merge pull request #2122 from dpeek/no-undefined-window-check

Don't check for undefined window in js.Browser (browsers have windows)
remove EUntyped from trace typing (closes #2128)
add Lambda.find
add TypeTools.findField
add TypeTools.applyTypeParameters
add MacroStringTools.toDotPath
add TypeTools.unify
add haxe.macro.Build.forwardAbstractFields
improve abstract meta handling
allow @:expose(field names) on abstracts
fixed using/abstract creating extra closures with iterator (closed #2129)
move add_feature to DCE (closes #2129)
use abstract implementation fields only in left-mode when detecting operator overloads (closes #2130)