pgAdmin 4 commit: Maintain a client-side cache of preference values, po

Maintain a client-side cache of preference values, populated using an async call. Fixes #2487

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=67fd119de834afd022f95c8c153a3b0c8c7b7fae
Author: Khushboo Vashi <khushboo(dot)vashi(at)enterprisedb(dot)com>

Modified Files
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.../browser/templates/browser/js/browser.js | 47 ++++++++++++++++------
web/pgadmin/preferences/__init__.py | 23 ++++++++++-
.../templates/preferences/preferences.js | 2 +
web/pgadmin/static/js/check_node_visibility.js | 19 +++------
4 files changed, 63 insertions(+), 28 deletions(-)