#52 Updated/extended release process page.

 - Divided page into 5 sections.
 - Added release record and GitLab milestone steps.
 - Added link to development process.
 - Added various requirements and other steps, like release reviews.
 - Added information on how to name the develop to master merge request.
 - Simplified GitLab tag/release creation instructions.
 - Extended Jenkins tag build/release instructions.