Update Deployment Document for MOSIP v1.2.1.0

[Varaniya201]

Release wise segregation of Deployment Documentation (v1.2.1.0)

[svahsek]

@ckm007 added a PR - #1162
This contains the new markdown to be added and segregated.
Gitbook is needed to create new topics/pages and move content by Chandra there.

[svahsek]

There are broken links - Check these, fix them and then publish the docs. Should be done this week between - Mon 22 - 26th June.

[svahsek]

Shared the list of broken links with DevOps (Abhishek Sahu) and have asked to fix and raise PR.

[svahsek]

Abhishek Sahu has corrected broken links and raised a PR - https://github.com/mosip/documentation/pull/1175/changes

[svahsek]

Asked @ckm007 and @bhumi46 to verify the links and raise PR