pgAdmin 4 commit: Refactor keyboard shortcut functions in the querytoo

Refactor keyboard shortcut functions in the query tool. Fix some incorrect keycodes and update docs.

Initial work by Sarah & Violet @ Pivotal, with additional tweaks by Murtuza @ EDB.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=b585063a26ba74d4ef48254b3ee41da2ba7cdcf9
Author: Sarah McAlear <smcalear@pivotal.io>

Modified Files
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docs/en_US/keyboard_shortcuts.rst                  |    6 +-
.../static/js/sqleditor/keyboard_shortcuts.js      |   36 +-
.../static/js/sqleditor/query_tool_actions.js      |   99 +
web/pgadmin/tools/datagrid/__init__.py             |    2 +-
.../tools/datagrid/templates/datagrid/index.html   |   26 +-
web/pgadmin/tools/sqleditor/static/js/sqleditor.js | 6671 ++++++++++----------
.../sqleditor/keyboard_shortcuts_spec.js           |  273 +-
.../sqleditor/query_tool_actions_spec.js           |  398 ++
8 files changed, 4000 insertions(+), 3511 deletions(-)