Unmount and text updating

Unmount, text updating and posibility to render single ComponentDescription added.
Simple selenium test.

And selenium configuration.
1 more test plus more functionality by utils.
Change implementation of children update.

Changed to use maps.
Key attribute added to component description and to it's factory
Added key to NodWithFacotry and rename it to NodeChild
Core working with keys, moving node children.
updated tests
Browser moving by keys done.

Plus some test enhacement.
Optimalization.
Merge pull request #10 from cleandart/feature/key

Key feature