pgAdmin 4 commit: Move security keys into the SQLite database, and auto

Move security keys into the SQLite database, and auto-generate them.

This avoids packagers having to deal with the issue, which can be
difficult if they need to cater for both server and desktop modes.

Fixes #1849

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=bc5cc964a3a67a0a5e367524c18e51266faf08f8

Modified Files
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web/config.py                 | 16 +++---------
web/pgAdmin4.py               | 12 ---------
web/pgadmin/__init__.py       | 31 +++++++++++++++++------
web/pgadmin/model/__init__.py |  9 ++++++-
web/setup.py                  | 58 +++++++++++++++++++++++++++++++++----------
5 files changed, 80 insertions(+), 46 deletions(-)