Proper isEqual and hash implementations for HAXElement
Initial implementation of HAXElement delegate support.

With support for element destruction notification.
nonnull attributes as appropriate for HAXElement methods
Merge branch 'develop' into numist/isEqual-and-hash
Merge branch 'develop' into numist/element-delegate
Merge branch 'develop' into numist/attributes
Merge pull request #18 from numist/numist/isEqual-and-hash

Proper isEqual and hash implementations for HAXElement
Merge pull request #20 from numist/numist/attributes

Add nonnull attributes as appropriate for HAXElement methods.
Merge pull request #19 from numist/numist/element-delegate

RFC: Initial implementation of HAXElement delegate support.