pgAdmin 4 commit: Add optional data point markers and mouse-over toolti

Add optional data point markers and mouse-over tooltips to display values on graphs. Fixes #3514
Ensure queries are no longer executed when dashboards are closed. Fixes #3576

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=a74b9c96c1e699816fb9f93c9a54a5e7373deeac
Author: Aditya Toshniwal <aditya(dot)toshniwal(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/release_notes_3_4.rst | 3 +
web/package.json | 3 +-
web/pgadmin/browser/static/js/panel.js | 9 +-
web/pgadmin/dashboard/__init__.py | 25 +++-
web/pgadmin/dashboard/static/js/charting.js | 99 ++++++++++++++
web/pgadmin/dashboard/static/js/dashboard.js | 147 +++++++++++++--------
.../javascript/dashboard/charting_spec.js | 91 +++++++++++++
web/webpack.config.js | 1 +
web/webpack.test.config.js | 3 +
web/yarn.lock | 6 +-
10 files changed, 324 insertions(+), 63 deletions(-)