Abstract the support for ORDER BY and LIMIT/OFFSET SQL generation all DB engines do not support the same syntax for these features, MS SQLServer being the bad boy we try to support in CW. * Use two new methods of dbhelper to add LIMIT/OFFSET clauses and ORDER BY clauses * added unit tests for sqlserver backend * changed unittest_rql2sql to lauch the backend tests even if the driver module is not installed on the machine, so that we can run the sqlserver tests on linux (and the mysql tests too) * adapt msstep.py to the new interface closes #1154756

backport oldstable

[migration] Lesser memory consumption of cwuri fix + actually commit every 100 processed entities Don't use the ORM as added value is poor while all intentiated object are keept by rset cache.

[migration] improve fix cwuri progress bar * Use the progress context manager, * Adds a title * Informs that operation have been partially committed.

[migration] explicit first step of 3.10.9 migration. Previously there was on a "commit now" confirmation. The reason of the request are now explained and both request must be confirmed.

cleanups

[uiprops, css] make header background actually modifiable through uiprops

[components] add **kwargs to render method of header components to make them usable as regular components (eg in other places than the header

[schema views] don't propose 'view all' action for final entity types (closes #1560549)

[doc] fix urls pointing to repositories and download sites

backported tag to stable

Added tag cubicweb-version-3.9.x for changeset 48f468f33704

merge

[devtools] missing py2.5 compat import

merge oldstable into default