pgAdmin 4 commit: Fix the file manager when used under Python 3. Fixes

Fix the file manager when used under Python 3. Fixes #1872

Issues fixed:

1) In Python 3, parameter "cmp" is removed from sorted method. So File Manager won't open.
As we are sorting data on JS side using Natural sort, so on server side sorting is not required.

2) Improvement in Exception handling.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=d806a9ce9ed269e53c256d747dba46810f78eb87
Author: Surinder Kumar <surinder.kumar@enterprisedb.com>

Modified Files
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web/pgadmin/misc/file_manager/__init__.py | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)