Basic implementation of different product properties types

Its right now just basic implementation and we together with @skowi working on it.

[x] String properties
[x] Boolean properties (validation need to be improved)
[x] Number properties
[x] Choice properties

There are problem with validation of boolean field. Basically checkbox which is unchecked is not send in POST. So maybe more sense will have to implement Yes/No "radio" instead of checkbox ?
We can implement define of other options for property types like "required" "label" itd.