automaticly outline a selection (fill up with spaces)

[xanderhermsen]

print "":
------- selection --------
print "":
print "":
----- end selection -----
print "":

now outline the selection so that it starts on the same column as in the previous line.

This is usefull when you are a programmer and copy a for loop under some other function which doesn't start on the same column because of for example some comparison with if.