Tabify and platform support

Number of things.

1)  Tabify the lib/*.rb scripts.   They were actually 1/2 and 1/2 so at least now they are consistent.  If someone wants spaces thats fine by me but mixing makes a mess.

2)  rake sln will now use xdg-open and open for linux and mac respectively.   I HAVE NOT TESTED mac. but at least it isn't as broken as start!

3)  storyteller ui rake tasks are never going to work on linux/mac with mono as mono doesn't support WPF.  Therefore I removed the tasks completely when running on those platforms.

4)  Replaced start with xterm and Terminal for linux and mac.   So executing commands should start in new console windows.  This is essentially the same behaviour as windows start.   Potentially more that could be done around this area ( like using the same console instead of just xterm )