[test] Use --short-description when testing newcube command

[devtools] Allow to specify short desc on `newcube` command line In order to implement automated testing of `cubicweb-ctl newcube`, we need to avoid any user interaction. So we add a `-s` switch to specify a short description on the command-line instead of requiring an input.

[pkg] Add new autopkgtest for skeleton packaging When running `cubicweb-ctl newcube`, the generated template provides debian packaging. So let's add automated tests for that using autopkgtest. The new test will generated a new cube, build a source tarball, build the package, try to install it, see if the Python 3 module is available and even run autopkgtest against the newly created packages. Along the way it will also print information about the generated package: buildinfo, package content, and lintian report.

[cubicweb-ctl] move to accepting only once instance name per command The rationals behind this decision are: - while in the past managing all instances sytem wide made a lot of sens, pratices have evolved today and we've moved to managing one instance by one - this makes things easier to debug since commands since using them on several instances were making this harder (errors hidden in the middle) - also solve the problem of the return code to have, before it was always 0 which prevented to do things like: ipython --pdb $(which cubicweb-ctl) $command $instance or shell scripts that used it - this simplify the code and is always good to take

[pkg] Run all unit tests in autopkgtest We previously forgot to copy `tox.ini` alongside the tests. As this file configures pytest pattern matching rules, we were not running quite a few tests. This is now fixed. The added tests required some adjustments in the Debian dependencies. Sadly, not all tests currently pass. It seems there are some ordering dependencies between the tests in regards to how data are loaded. Fixing this probably would probably be better debugged by ensuring the test suite does not fail when using pytest random-order plugin.

[pkg] Stop running unit tests from skeleton The test files shipped as part as the skeleton for `cubeweb-ctl newcube` are not meant to be run as part of our test suite!

[tests] Use 16 bytes key when testing Blowfish The version of Cryptodome currently in Debian only accepts Blowfish keys with at least 5 bytes. This is a bug (it should accept 4 as it did before) that has since been fixed upstream: https://github.com/Legrandin/pycryptodome/commit/93912230f3c39e09f4038cb17e301468687c6538 So we work around this issue by using a 16 bytes key instead (which happens to be the minimum recommended length).

Use time.process_time() instead of deprecated clock() This fixes: DeprecationWarning: time.clock has been deprecated in Python 3.3 and will be removed from Python 3.8: use time.perf_counter or time.process_time instead

[web] Make the time separator configurable in JQueryDateTimePicker We add a "separator" argument to JQueryDateTimePicker which will be used when creating the underlying JQueryTimePicker instance so that the user can control how time is displayed by the widget. This is very similar to the "timesteps" argument that's already present.

Added tag 3.26.12, debian/3.26.12-1 for changeset 4531a266f8b2