Deprecate KNOXTOKEN API v1

In KNOX-2661, the following REST API endpoint changes happened:

• renew was updated from POST to PUT
• revoke was updated from POST to DELETE

Unfortunately, at that time I did not consider backward compatibility and I introduced a backward compatibility issue for clients using previous versions.

The scope of this Jira is to revert that issue back in the following way:

• change renew/revoke back to POST in '.../api/v1/token' in v1 (to fix the issue we introduced earlier)
• introduce v2 that will match v1, except that v2 will match the above changes from KNOX-2661
• mark v1 deprecated