Allow TinyMessenger to be used in PCL code 

Hi @Grumpydev

Unfortunately the PCL Generic `List<T>` doesn't implement `ForEach` 

This change simply replaces the two ForEach calls with foreach iterations instead.

Sadly, the change also stuffs up the formatting (sorry - on a Mac right now and MonoDevelop hates me).

If you want the contents of this Pull, let me know and I'll try to correct the formatting when I'm back on the PC :)

Stuart (@slodge)