Fixed creation of choice values for unselected (not required) options, fixed list attributes in the same case.
Changed choice values to not display group, as there was too much clutter on lists.
Changed the display of missing options on lists from "None" to a translatable "none" string.
Merge branch 'feature/configurable-products' into develop
Fixed choice values display in language different than the one they've been created with.
Fixed attribute value and image value initialization.
Merge branch 'feature/configurable-products' into develop