Support shareShadow option for connect

[cui-liqiang]

Only connect got affected.

1. If option is given, deployment name will be fixed as "kt-connect-daemon-connect-shared" instead of having random suffix
2. The shared shadow deployment will have a label named "refCount" to indicate how many clients are using it.
3. Store both public and private key in config map, so that latter clients can reuse it.
4. When client reuses the shadow, increase the refCount label value
5. When tear down, read the refCount label and decide to delete it or reduce the refCount.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

liqiang.clq seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}