pgAdmin 4 commit: Add keyboard navigation in Query tool module via Tab/

Add keyboard navigation in Query tool module via Tab/Shift-Tab key. Fixes #2896

Note:
1) Once the keyboard shortcut infrastructure is ready we will add generic shortcut to focus out from CodeMirror editor and set foucs to next element, Right now there is no way of doing this, For testing purpose you can manually focus out from CodeMirror and click on data output panel to continue navigate using Tab key.
2) As of now inner panel's are not getting focused on Tab/Shift-Tab keys but once RM#2895 patch gets committed it will start working automatically as it's inherited code which will add tabindex tag automatically on each newly created wcDocker panel.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=97760d65c2a8a3d22c16cfe0098f1e81f35d7791
Author: Murtuza Zabuawala <murtuza(dot)zabuawala(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/keyboard_shortcuts.rst | 47 +++++---
web/pgadmin/misc/static/explain/js/explain.js | 3 +
web/pgadmin/static/js/keyboard_shortcuts.js | 62 +++++++++-
.../static/js/sqleditor/keyboard_shortcuts.js | 81 -------------
.../jsx/history/detail/history_detail_query.jsx | 3 +
web/pgadmin/tools/datagrid/static/js/datagrid.js | 3 +-
.../tools/datagrid/templates/datagrid/filter.html | 2 +-
.../tools/datagrid/templates/datagrid/index.html | 130 ++++++++++-----------
.../tools/sqleditor/static/css/sqleditor.css | 5 +
web/pgadmin/tools/sqleditor/static/js/sqleditor.js | 47 +++++---
.../sqleditor/keyboard_shortcuts_spec.js | 44 +++----
11 files changed, 228 insertions(+), 199 deletions(-)