pgAdmin 4 commit: Added support to import/export server groups and serv

Added support to import/export server groups and servers from GUI. Fixes #4803

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=9dd957a2aa8f9f5286ae909621bad59944194b37

Modified Files
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.../images/import_export_servers_refresh_tree.png | Bin 0 -> 42683 bytes
docs/en_US/images/import_export_servers_step1.png | Bin 0 -> 81277 bytes
docs/en_US/images/import_export_servers_step2.png | Bin 0 -> 97491 bytes
docs/en_US/images/import_export_servers_step3.png | Bin 0 -> 82423 bytes
docs/en_US/import_export_servers.rst | 66 +++-
docs/en_US/release_notes_6_4.rst | 3 +-
docs/en_US/tree_control.rst | 2 +-
web/package.json | 1 +
web/pgadmin/static/css/style.css | 1 +
web/pgadmin/static/js/components/CheckBoxTree.jsx | 73 ++++
.../tools/import_export_servers/__init__.py | 201 +++++++++++
.../static/js/ImportExportServers.jsx | 259 +++++++++++++++
.../static/js/import_export_selection.ui.js | 98 ++++++
.../static/js/import_export_servers.js | 124 +++++++
.../tools/import_export_servers/static/js/index.js | 20 ++
web/pgadmin/utils/__init__.py | 370 ++++++++++++++++++++-
web/pgadmin/utils/constants.py | 1 +
.../import_export_servers.ui.spec.js | 68 ++++
web/setup.py | 322 +-----------------
web/webpack.config.js | 1 +
web/webpack.shim.js | 1 +
web/yarn.lock | 17 +-
22 files changed, 1298 insertions(+), 330 deletions(-)