Changed resrun to print No result if the program did not output anything...

Hi!

I changed the resrun to say `No result!` if the program does not output anything. This may happen in cases when the user writes a code which does some declarations, computation etc. and does not output anything (rarely, but may forget to do so). This is kept in sync with what the program outputs when nothing has been run. 

Did a small change in the rescomp for Python, since it can always be set to 'No Compilation Needed', instead of displaying a blank string.

Let me know if I did something wrong.

Best,
Sukrit