Log Message:
Update mtr to 0.71:

0.71:

The build-time check for the resolver library was improved. Binding
to a specific interface was fixed.  Incorrect display of multiple
routes was fixed. Several minor bugs were fixed.

  v0.70 Antinio submitted a cumulative patch containing some
        nice improvements. He also submitted an automake patch
        that causes mtr to no longer compile on my system. I
        refuse to have mtr "in the dark" that I can't test-compile
        the dist.

Add option for gtk support, and remove mtr-gtk package.