[server] commit after serializing schema Use separate transactions for schema serialization and postcreate scripts execution, so that the latter can rely on the schema being persistently stored. This matters e.g. if something in a postcreate violates a unique_together constraint, we need the constraint persisted in order to raise a meaningful error. See #4525069.

[book] fix docstrings to please sphinx example rst roles in docstring must be protected (in a literal).

[book] several fixes in the rst files - prevent duplicate markup definitions, - use existing Workflow markup instead of redefining one (in baseschema.rst) - include dataimport - fix non-existant directive autodocfunction - remove the empty 'embedding.rst' file

[book] activate the viewcode extension Automagically make link to class/modules/etc. it finds in the documents.

[book] new theme based on pyramid theme (closes #4291287)

Remove unused lgc.interface imports and leftovers

[repository] provide a .new_session entry point The current .connect only returns a `sessionid` which must be given to repo._get_session(...) to get the real session object. Related to #4151635.

[devtools/testlib] Use actual 'admin' user configuration values Previously ``db-user`` and ``db-password`` configuration values were used to fill ``admlogin`` and `admpassword`` attributes of CubicWebTC. The correct data for these should read from `[admin]` section. Closes #4065070.

[forms] closes #2437859 - Detect and prevent concurrent edition of the same entity. Add the timestamp of form generation to each entity's meta-information fields. On form validation, check that no concurrent change is overwritten and raises a ValidationError in case of concurrent change. A nicer handling with a message and a link to the new version of the entity would be a good thing...

[migration] make sure the repo knows about all constraint types Adding new constraint types is cumbersome. It's easy to forget to do it in a migration script. So sync the constraint types at the beginning of each migration. Closes #3724892

[migration] stop caching the mapping from constraint type name to eid It's not so frequent that a cache seems necessary, and we were not invalidating that cache when adding a new constraint type. Related to #3724892.

[web/json] an empty rset is just fine for ejsonexport The ejsonexport view can just return an empty list for an empty rset. Closes #4005518

[RichString] Add markdown support Supporting markdown requires the 'Markdown' python packages, and since it widely available on the target platforms adding it as a strong requirements will not be a big constraint. Closes #3814302

[ldapfeed] Reduce default value for user-attrs-map option (closes #3824889) This is needed because lgc.configuration.Configuration does not allow removing key/value pairs from the default (due to its use of dict.update() internally). Since CWUser.login is required, users of the add-source command will always be able to override it.

[serverctl] Ask for URL when adding a new source (closes #3824868)