Postpone date of users validation and clean out layer profiles after a crash

Closes #540

See merge request !312

Cleanup model representation

See merge request !314

__unicode__ is a leftover of Python 2

__unicode__ is a leftover of Python 2

__unicode__ is a leftover of Python 2

Consider updating algorithm to create activation key

__unicode__ is a leftover of Python 2

__unicode__ is a leftover of Python 2

Don't make the test database in memory for beat.cmdline tests

See merge request !311

For testing purpose the database has been moved to
/dev/shm and the sqlite3 file is used to optimize
the testing speed of beat/beat.cmdline.

removing Biometrics Evaluation from BEAT definition.

Closes #512

See merge request !310

Fix all the beat dependencies used for CI testing to match the versions used by buildout

See merge request !309

- beat.core 1.9.0
- beat.backend.python 1.7.2
- beat.cmdline 1.5.0

Since beat.core is fixed at 1.8.0, the others must also
be pinned to their corresponding versions.

See release.cfg

[docs] added validation prodedure for web interface Bug 485 to the admin documentation

See merge request !308

Fix report's experiment table name/URL construction & restrictions

Closes #531 and #532

See merge request !297