pgAdmin 4 commit: Allow dashboard tables and charts to beenabled/disab

Allow dashboard tables and charts to be enabled/disabled. Fixes #2951

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=801a2084e9337e4bf07355a074f3adfbdcb9a334
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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.../en_US/images/preferences_dashboard_display.png |  Bin 0 -> 333609 bytes
docs/en_US/preferences.rst                         |    8 +
web/pgadmin/dashboard/__init__.py                  |   28 +-
web/pgadmin/dashboard/static/js/dashboard.js       | 1130 ++++++++++----------
.../templates/dashboard/database_dashboard.html    |   32 +-
.../templates/dashboard/server_dashboard.html      |   31 +-
web/pgadmin/dashboard/tests/__init__.py            |    8 +
.../dashboard/tests/test_dashboard_templates.py    |  279 +++++
8 files changed, 958 insertions(+), 558 deletions(-)