pgAdmin 4 commit: Prevent the user attempting to run external commands

Prevent the user attempting to run external commands if the bin path is not configured. Fixes #1177

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=f78024808e80fef67de1aef5c97d1756c6771c0e
Author: Harshal Dhumal <harshal.dhumal@enterprisedb.com>

Modified Files
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.../browser/templates/browser/js/browser.js        | 17 +++++
web/pgadmin/preferences/__init__.py                | 27 ++++++-
.../tools/backup/templates/backup/js/backup.js     | 86 ++++++++++++++++++++++
.../templates/import_export/js/import_export.js    | 43 +++++++++++
.../templates/maintenance/js/maintenance.js        | 47 +++++++++++-
.../tools/restore/templates/restore/js/restore.js  | 44 +++++++++++
web/pgadmin/utils/preferences.py                   | 13 ++--
7 files changed, 265 insertions(+), 12 deletions(-)