Update link to Forums

Note from Jennifer:
On Dec 13, 2016, at 5:17 PM, Jennifer Garcia <Jennifer.Garcia@couchbase.com> wrote:

Hi Amarantha,

Can you help me with who could update these documentation pages with correct links?

This bad link:

https://www.couchbase.com/forums/user/register

Is on these pages:

http://developer.couchbase.com/documentation/server/4.5/release-notes/giving-feedback.html, http://developer.couchbase.com/documentation/server/4.1/release-notes/giving-feedback.html, http://developer.couchbase.com/documentation/server/4.0/release-notes/giving-feedback.html, http://developer.couchbase.com/documentation/server/current/release-notes/giving-feedback.html

The correct link is:

https://www.couchbase.com/register?url=https://forums.couchbase.com/auth/jwt/callback