Remove replace directive in go.mod

[LouisPlisso]

Hi,
We are trying to import the operator-sdk in our repo to be able to run operator-sdk based tests.

Because of the replace directive in go.mod, this breaks our build and we are currently blocked.

Since k8s repos now offer a "native" way to pin versions k8s 1.16.7 maps to a go.mod version of v0.16.7, we can achieve the pinning to a particular kubernetes version without using the replace directive.

I got the operator-registry to build without replace directive in go.mod on my local branch (pointing at the non-pinned k8s version for the api repo, on top of operator-framework/api#17).

Do you want me to create a PR for this work? Not that this would need the PR in api repo to be merged and released as 0.1.1

Note that my overall goal is to not have replace directive for k8s in operator-sdk so that it will be easier to import for ever user

[LouisPlisso]

addressed by #212

[LouisPlisso]

@ecordell can you please release the change in #212 so that we can import operator-sdk without conflicts on k8s versions (or replace directive in go.mod)?

[LouisPlisso]

Thanks for releasing this :)