Introduced common abstraction for array and observable array.
Fixed bugs.
Added 'beforeRender' method.
Introduced abstract array.
Fixed replacement bug with children.set(...). Fixed bug with replaceWith which removed all elements event listeners.
Array adjustements.
Merge branch 'jw-array' of github.com:enepomnyaschih/jwidget into jw-array
Adjusted sets and maps to common JW.AbstractCollection interface.
Documentation
Fixed bugs.
Added JW.AbstractMap.getJson.
Merge branch 'jw-array' of github.com:enepomnyaschih/jwidget into jw-array