[view] fix TypeError when calling req.view('vid', entity=entity) (closes #1947474)

[sources management] nicer source management view and breadcrumbs (closes #1946329) * nice 'add host config button' * table displaying host configuration * display a source's config using <pre> or something like that that respects EOL * configure breadcrumbs for CWSourceSchemaConfig and CWSourceHostConfig

[cubicweb.js] log evalJSON errors (closes #1947473)

[views/table] parametrize table view co-classes (closes #1947472)

[cwproperties] refactor properties form to make it partly overrideable easily (closes #1936782) also fix some pitfalls on the way: * shouldn't capitalize labels, this has to be done in translation files as desired * form_row in CWProperties form didn't return subform as its parent class

[entity] rename Entity._rest_attr_info into cw_rest_attr_info (closes #1942759)

[entity] upgrade fetch_[unrelated_]order to benefit from changes introduced in 3.14 (closes #1942758) of rql generation parts of the ORM now based on rql syntax tree. This allows more powerful and flexible sort control by giving them the syntax tree instead of manipulating string. Also: * prefix new methods by 'cw_' * fix cases that currently crash in 3.14 due to the refactoring

[schema] drop CWSourceSchemaConfig[cw_for_source,cw_schema] unique constraint (closes #1946277) as they are not necessarily unique, eg when one want a configuration for both subject and object

[cleanup]

[jsoncontroller] deprecate the now unused js_set_cookie (closes #1944810)

[repo] ensure we don't restart a task while the repo is shutting down (closes #1942736) we need a safety belt in cw itself again looping task which use 'try / except' or doesn't need to access the db (which will trigger ShuttingDown exception)

[warnings] explicitly ask to show DeprecationWarning in debug mode (closes #1942760) as python 2.7 don't show DeprecationWarning by default