Add go.mod file

[odeke-em]

Go mod initiated

Fixes #11

[odeke-em]

/cc @someone1, please let me know if this cuts the deal for you.

[someone1]

I'll be the first to admit that I'm no expert with go mod 😅

That said, since this branch is already tagged for V2 (instead of a v2 branch), I think you'd want to define the module as module github.com/opencensus-integrations/redigo/v2 - though I could be mistaken.

Here is a resource that may help: https://research.swtch.com/vgo-module

[someone1]

The more I think about it, adding the v2 suffix is appropriate here since it should work off of the tags - even without the go.mod file the updated tag makes this repository useable now!

I don't see any dependencies though - I think that'd be the main benefit using go.mod here?

EDIT - to clarify, the use of go mod doesn't break this package anymore with the new tag, however, you still can't do an import like github.com/opencensus-integrations/redigo/v2 - perhaps adding the file, even without explicit requirements, would fix this

[vtopc]

Where are

"go.opencensus.io/stats"
"go.opencensus.io/tag"
"go.opencensus.io/trace"

and other deps?