Migrate to go modules

[kishaningithub]

I see the project still uses go dep (https://github.com/mefellows/muxy/tree/master/Godeps)

Any specific reason for the same?

I recommend moving to go modules, I am happy to help

[mefellows]

Apologies, I somehow missed this - yeah all for that move.

If you're up for a PR I'd be happy to accept :)