[test] get a chance to get proper garbage collection when running pytest on whole cw

[testlib] properly close dumb sessions

[debug] more (dirty) gc debuging

custom rest publisher instead of using rest_publish. Avoid to keep a ref on the latest context

cleanup

[rest] cleanup, avoid deprecation warning

delete pyro proxy on connection close, properly raise programming error when working on a closed connection

cleanup

[test] get a chance to get proper garbage collection when running pytest on whole cw

more tests

[repo] improve planning of insert/update queries: do not select affected constants so the don't go and back to/from the source.

schema serialization optimization by using eids instead of type names. Heavy refactoring/cleanup on the way

backport stable

[testlib] automatic test shouldn't try to populate default_workflow

minor schema serialization optimization: * remove verbose handling, no more necessary since server.set_debug * remove old bw compat code * other cleanups