pgAdmin 4 commit: Add support for connecting using pg_service.conffile

Add support for connecting using pg_service.conf files. Fixes #3140

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=03b772bf642d2364c3c51226da4b33439107e883
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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docs/en_US/images/server_connection.png            |  Bin 39678 -> 66243 bytes
docs/en_US/server_dialog.rst                       |    1 +
web/migrations/versions/50aad68f99c2_.py           |   82 +
.../browser/server_groups/servers/__init__.py      |   61 +-
.../server_groups/servers/static/js/server.js      |   48 +-
.../tests/test_add_server_with_service_id.py       |   47 +
web/pgadmin/model/__init__.py                      |    5 +-
web/pgadmin/utils/driver/psycopg2/__init__.py      | 1985 +-------------------
web/pgadmin/utils/driver/psycopg2/connection.py    | 1682 +++++++++++++++++
.../utils/driver/psycopg2/server_manager.py        |  333 ++++
10 files changed, 2227 insertions(+), 2017 deletions(-)