pgAdmin 4 commit: Resolving few issues with the drop/drop cascade objec

Resolving few issues with the drop/drop cascade object function at front-end.
Also, modified the translation messages as per Dave (Thanks Akshay Joshi for the patch).

Modified the way, we show the error message dialog.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=7beaefd1c6eb9e3b9e70c2bd72358a9de7d6f888

Modified Files
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web/pgadmin/browser/templates/browser/js/error.js |  6 +--
web/pgadmin/browser/templates/browser/js/node.js  | 46 +++++++++++++----------
web/pgadmin/templates/base.html                   |  2 +-
3 files changed, 30 insertions(+), 24 deletions(-)