version 0.0.3a and showcase ready

[Bulat Sirazetdinov]

You now can see the showcase of the editor at: http://formula-editor.appspot.com/

Source code version 0.0.3a is uploaded into repository and to a
showcase. Editing formula now places entered elements in a correct
order. You can insert variables, +-*(), divisions and edit powers.
Still no insertion of the functions, no deletion of entered elements
and no code completion.