pgAdmin 4 commit: Re-hash the way that we handle rendering of specialt

Re-hash the way that we handle rendering of special types such as arrays. Fixes #2782. Fixes #2822.

Branch
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WEBPACK_DEVEL2

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=444589a58dbb98a58a69a6399cbbf7d38aedb497
Author: Harshal Dhumal <harshal.dhumal@enterprisedb.com>

Modified Files
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web/pgadmin/feature_tests/test_data.json           |   6 +-
web/pgadmin/static/js/slickgrid/editors.js         |  55 +----
web/pgadmin/static/js/slickgrid/formatters.js      |  69 ------
web/pgadmin/tools/datagrid/__init__.py             |   3 +-
web/pgadmin/tools/sqleditor/__init__.py            |   7 +-
web/pgadmin/tools/sqleditor/static/js/sqleditor.js |   8 +-
web/pgadmin/utils/driver/psycopg2/__init__.py      | 159 ++-----------
web/pgadmin/utils/driver/psycopg2/cursor.py        |   4 +-
web/pgadmin/utils/driver/psycopg2/typecast.py      | 250 +++++++++++++++++++++
9 files changed, 295 insertions(+), 266 deletions(-)