IBX-88: [Rebranding] Renamed ezpublish extension to ibexa

[alongosz]

Question	Answer
JIRA issue	IBX-88
Requires	ibexa/compatibility-layer#3
Type	feature
Target Ibexa version	v4.0
BC breaks	yes, requires ibexa/compatibility-layer#3

Core change:

• 2a45370

With Ibexa Compatibility Layer Bundle it should be enough to run a fresh project installation, without 1st party changes.

There are also other changes getting rid of extension-related (directly and not directly) strings containing ezpublish. The ones prepending config and changing suggestions format are necessary, the others are cosmetic.

Aiming to merge it quickly to unblock further work, with possible follow-ups if something comes up by future QA tests.

Checklist:

• Provided PR description.
• Tested the solution manually.
• Aligned automated test coverage.
• Checked that target branch is set correctly
• Ran PHP CS Fixer for new PHP code
• Asked for a review (ping @ibexa/engineering).

[alongosz]

CI failure appears on the main branch also, needs to be investigated separately. Merging. Aiming for QA at the end of the whole set of rebranding-related changes.