[predicates] Simplify specified_etype_implements

[web/views] Fix `has_editable_relation` predicate wrt inlined relations Prevents the "modify" action from being shown when there is nothing to edit.

[web/views] avoid propagation of NoSelectableObject in some case of inlined relations / permissions When selecting an inlined creation form, we should catch the NoSelectable exception that will be raised if the user cannot add entities of the target type (this is not and cannot be verified earlier) or if some other custom selector prevents the form from being selected. Closes #6510921

[server/test] bit of PEP8

[migration] don't attempt to carry over values when renaming a computed relation Without the fix in migractions.py, the introduced test crashes with an operational error because of an attempt to write to a non-existing relation table (computed relations are not materialized). Closes #6304946

consider .do_fti flag in index_entity method as this method may be used from outsite the class (eg in UpdateFTIHook), this is the proper way to consider it anyway. Closes #6206636

Added tag 3.19.13, debian/3.19.13-1, centos/3.19.13-1 for changeset f933a38d7ab5

[pkg] 3.19.13

[migration/3.21] add support for sqlserver Closes #7173702

moved_entities.extid may not be NULL

[server] use sqls_create_multicol_unique_index to index entities.extid SQL Server's UNIQUE is not standards compliant, it doesn't accept two NULL values. Related to #7173702.

[server] fix checkintegrity with pyodbc "msg % row" dies with "not enough arguments for format string" if row is a pyodbc.Row.

[schema] remove unique constraint on unlimited String attribute SQL Server doesn't allow indexing (and thus unique constraints) on nvarchar(max). Related to #7173702.

[sources/native] fix potential NameError (closes #7364249)

[py3k] unicode → six.text_type

[devtools/testlib] Port CubicWebTC.view() to py3k testlib.TestCase.set_description's argument will eventually be printed out to sys.stdout/stderr. On python 2, this object takes bytes-like objects (eg, str) whereas python 3's takes unicode-like objects and handles the encoding on its own. Thus the 'str' type can used in both versions to eventually display the description on screen.

[devtools/testlib] port 'fake_form' test to io.BytesIO

[dataimport] port ucsvreader tests to io.BytesIO

[py3k] io.BytesIO

[py3k] io.StringIO

Port cw.Binary to io.BytesIO And add plenty of tests too!

[py3k] execfile → exec

[py3k] file → open

[py3k] six.integer_types

[py3k] basestring → six.string_types

[py3k] import CookieJar using six.moves

[py3k] import urllib2 from six.moves

[py3k] import range using six.moves

[py3k] import queue using six.moves

[py3k] import filter using six.moves