Added rotate function at the CQ object level and an associated test

I was using rotate and translate in a project and noticed that while there was a translate function at the CQ class level, there was no rotate function. This forced me to drop out of the higher CQ level with a val(), and then I couldn't call .toFreecad() on the resulting object after rotation and translation. 

This was not a bug fix, just something to make working with CQ syntax a little cleaner.