Generate api information in OpenAPI model and register types to scheme

[jetmuffin]

The Install function will be used when generating OpenAPI specification for Java/Python client. See my last PR for more detail #719 .

Signed-off-by: JetMuffin mofeng.cj@alibaba-inc.com

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This change is 

[TravisBuddy]

Travis tests have failed

Hey @jetmuffin,
Please read the following log in order to understand the failure reason.
It'll be awesome if you fix what's wrong and commit the changes.

2nd Build

gometalinter --config=linter_config.json --vendor ./...

pkg/apis/tensorflow/v1alpha2/install.go:1::warning: file is not goimported (goimports)

3rd Build

gometalinter --config=linter_config.json --vendor ./...

pkg/apis/tensorflow/v1alpha2/install.go:1::warning: file is not goimported (goimports)

travis_time:end:015076c8:start=1531819928738968933,finish=1531820074953840826,duration=146214871893

[coveralls]

Coverage decreased (-0.3%) to 56.923% when pulling 6faaee9 on JetMuffin:install into bb60bfa on kubeflow:master.

[ScorpioCPH]

/ok-to-test

[gaocegege]

/lgtm
/approve

[k8s-ci-robot]

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