tasks #7082: Enhance update

 * Update custom date metadata & hardcoded metadata
 * Fix permission
 * Refactoring

Change-Id: I15220769eed18cec7d696df9ca08d20ef25339a0
Merge commit 'refs/changes/66/2666/2' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  tasks #7082: Enhance update

Change-Id: I0beec322284c9e56c78451c3d7490aedad085257
This is Tuleap 7.1.99.48

Change-Id: I0d78a1b00e83e35d98c2857b111b176664512afa