TNS platform clean android  #2496

I ran into a corner case; but one that is annoying if you aren't paying attention.

If you are building a product using a prior version of the runtime; lets say 2.4.1 and you do a
tns platform clean android you will end up with 2.5.0 of the runtime. When I do a "clean" I expect to maintain the SAME version of the runtimes; I don't expect to have part of my project upgraded...