pgAdmin 4 commit: Add infrastructure for managing configurablekeyboard

Add infrastructure for managing configurable keyboard shortcuts.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=66341e6947b0999b66c46078bf31f89851597fd6
Author: Harshal Dhumal <harshal.dhumal@enterprisedb.com>

Modified Files
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web/pgadmin/preferences/static/css/preferences.css |  16 +-
web/pgadmin/preferences/static/js/preferences.js   |   2 +
web/pgadmin/static/js/backform.pgadmin.js          | 201 ++++++++++
web/pgadmin/utils/preferences.py                   |  32 +-
.../backform_controls/keyboardshortcut_spec.js     | 434 +++++++++++++++++++++
.../javascript/backform_controls/keycode_spec.js   | 199 ++++++++++
web/webpack.test.config.js                         |  10 +
7 files changed, 885 insertions(+), 9 deletions(-)