3.0.0

• all : added haxe.ds.BalancedTree
• all : added haxe.ds.EnumValueMap
• all : allow enum constructors as keys to Map
• all : haxe.ds.ObjectMap is now correctly constrained on all targets
• all : preliminary support of -D display-mode=usage|position|metadata
• all : improved pattern matcher error messages
• all : allow inline constructors
• all : allow abstract member macros (not for @:op, @:arrayAccess, @:from, @:to)
• all : allow abstract type parameter variance
• all : do not generate hidden null on if without else
• macro : made abstract structure available