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Postgresql

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Cleanup auto-completion and add it to all GFM inputs

Fix forward/back while browsing Tree hierarchy

* static initialization and setup moved to assets
* per request initialization moved to layout partial

Closes #1578

Improve completion of emoji and team members 

Refactoring

Fix messages for deleted things on dashboard

This reverts commit 927d0cc2.

Do not allow removal of a project owner user.

Tree performance improvements