Render all label-col-xx classes in horizontal mode

[NicolaIsotta]

Right now, only one of the classes specified by the user is rendered: for example, if I have a b:inputText with label-col-sm="4" label-col-md="3" label-col-lg="2" the generated html contains this: <label class="bf-no-message has-success col-md-3 control-label" [...] >.
The issue is in the class net.bootsfaces.render.Responsive, method getResponsiveLabelClass: the strings for the col-xx classes should be combined in a StringBuilder.

[stephanrauh]

Good point. I've fixed that. Thanks!

[stephanrauh]

I've published a developer snapshot on Maven Central. As usual, see #369 on how to get it.