[migration] reorder system tables / meta-schema migration into bootstrap_migration
Also fix a bug in the backwards-compat eid_type_source method where it
returned an extid (possibly null) instead of a source name.
With these changes, migrating a database from cw 3.12 is now possible.
Closes #4962681
.. winclude:: search_sample_queries
You can as well type complex queries using the RQL_ query language,
used every where to build dynamic pages of this site.
You can use one of the following prefixes to specify which kind of search you
want:
* `rql` : RQL query
* `text` : full text search
.. _RQL: tut_rql