[hook] fix name error in case of error on hook's .event checking

[ms] fix planning bug introduced with recent rql refactoring for queries with only eids (fix unittest_multisources.test_in_eid)

[hook] proper bad .events detection. Fix unittest_hook

backport stable

[test] _gc_debug deleted from etwist.server

[doc/book] talk about reloadComponent, misc tweaks and notes

[doc/book] add q/a on i18n customisation, misc tweaks

Switched from TwistedWeb2 to TwistedWeb - added HTTPResponse class in etwist/http.py (could be then abstracted in cubicweb/web) - added twisted.web2 http_headers.py file in cubicweb/web to handle HTTP headers conversion between raw headers and python object - deleted caching for base views (except for startup views). A better solution would be using weak entity tags (but they don't seem to be implemented in twisted.web). - added forbidden access message when browsing static local directories - tested with TwistedWeb 8, 9 and 10 TODO: ===== - Handle file uploading in forms. twisted.web seems to keep very little information (only file content) about uploaded files in twisted_request.args['input_field_name']. But it doesn't seem to keep track of filenames. Possible solutions : - use web2 code to parse raw request content still stored and available in twisted_request.content - find a magic function in twisted.web API to get the filenames - More tests.

merge

[ldap] fix email synchronization code: bad rql query + avoid integrity error on creating the address + nicer use_email / primary_email handling