Switch glide to go modules for dependency management

[feiskyer]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespaces from that line:

/kind api-change
/kind bug
/kind cleanup
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

/kind feature

What this PR does / why we need it:

Kubernetes master branch has been switched to go modules. This PR switches current glide to go modules for dependency management.

Which issue(s) this PR fixes:

Fixes #101

Special notes for your reviewer:

Refer kubernetes/kubernetes#74877 and https://github.com/kubernetes/enhancements/blob/master/keps/sig-architecture/2019-03-19-go-modules.md.

Release note:

Switch glide to go modules for dependency management.

[feiskyer]

/assign @andyzhangx @ritazh

[andyzhangx]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andyzhangx, feiskyer

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [andyzhangx,feiskyer]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment