BUGFIX: Two global flags can be appreviated to -v, causing confusion

[tlimoncelli]

Issue

Two global flags can be abbreviated to -v. Both --debug and --version can be abbreviated to -v. This causes confusion (example: #4138).

The "global options" section of dnscontrol -h shows:

GLOBAL OPTIONS:
   --debug, -v        Enable debug logging
   --allow-fetch      Enable JS fetch(), dangerous on untrusted code!
   --disableordering  Disables update reordering
   --no-colors        Disable colors
   --help, -h         show help
   --version, -v      print the version

Resolution

Remove -v from --debug. The flag parsing module we use really really really wants to own the -v flag.