[schema] introduce some new sets categorizing entity/relation types and benefits from them where possible

backport stable

[schema] introduce new WORKFLOW_RTYPES set and use it to build SYSTEM_RTYPES/DONT_CHECK_RTYPES_ON_ADD/DONT_CHECK_RTYPES_ON_DEL sets

[rset] support for delitem on repeat list (may be necessary in pyro source)

merged timeline changes into default

timeline view minor enhancements * support dates < 1900 by using logilab.common.date.ustrftime * make the timeline a public member of the TimeLineWidget * let buildWidget return the created widget, so that we can manipulate it later

fix bad merge

backport stable

[test] more update to unittest2 api

[repo] properly mark object as saved once added to its source (code much probably gone during a merge...)

fix merge, some buffers weren't saved...

backport stable

[test] must now commit file creation since the later ValidationError trigger a rollback

cleanup and micro-optimization

[web action] has_editable_relations should not filter out final relations, fix regression introduced in 6358:22c95c5ef12d

[c-c] fix RuntimeError: 'maximum recursion depth exceeded while calling a Python object' we get when creating/upgrading/shelling an instance: hasattr() call __getattribute__, creating an infinite recursion error catched by the interpretor. Avoid this by testing the method is available on the class instead of the instance

[transaction] to avoid potential db corruption, we should rollback systematically in case of ValidationError

[selector] cleanup

[sync schema] take care rdef may not be final, in which case we want to use type of eid attribute

[web action] has_permission_update checked implicitly by has_editable_relation, don't check it twice

[muledit] form may contains subforms with nothing editable that will be s kipped, so ensure we choose one with something to display when rendering table headers

[c-c i18n] namespace/line wrap cleanup + dynamically compute available language + make it works in installed mode

[i18n] no more necessary, those msgids are no more generated

[wf component] reversing selectors here may be a huge performance win on big rsets, since EntityVComponent selector starts with one_line_rset