Remove v2 versioning

[mkumatag]

Fixes: #241

[AlecAivazis]

As I said in #241, we're not going to remove the v2 in the import path since it would break user's bilds

[tsingson]

As I said in #241, we're not going to remove the v2 in the import path since it would break user's bilds

yes, don't do this. we use v2 in product for half year............. it's work great.