Dropping wiki

[legalsylvain]

Hi @OCA/openupgrade-maintainers

As explained in this PR, I think the current wiki should be dropped as it is very obsolete and not visible.

So far,

• I created a backup of the current wiki. (readonly) https://github.com/grap/openupgrade_wiki_backup
• Dropped the following page, in the OpenUpgrade wiki:
  • Migration-from-7.0-to-8.0.md
  • Migration-from-Launchpad-to-Github-of-7.0-branch.md
  • Planned migrations.textile
  • Set-up-the-branch-for-a-new-Odoo-release.md

Pending Work

• How-to-create-a-reference-database.md : [ADD] documentation for OpenUpgrade manager. how to create reference database. #4575

Todo / Remaining work

Move into OCA/OpenUpgrade Documentation branch :

• Crude-script-to-create-the-full-analysis-between-two-versions-of-Odoo.md