Add --rotate option

[AntonPetrov]

Traveler supports the --rotate option. In my tests, using it globally is not helpful as it works well in some cases and does not in others. However, it could be a command line/website option that the users can try manually.

Example improvements:

Mixed results:

Proposed action:

• add optional flag r2dt.py --rotate
• the flag should add --rotate to all traveler commands (in both template and template free modes).