pgAdmin 4 commit: Added PSQL tool support for the Windows platform.

Added PSQL tool support for the Windows platform. Fixed following issues: 1. If the database name contains escape characters then PSQL unable to connect. 2. If the user terminates the connection by typing the 'exit' command, PSQL will show the connection termination msg. Fixes #2341 Branches

pgAdmin 4 commit: Added PSQL tool support for the Windows platform.

Added PSQL tool support for the Windows platform. Fixed following issues: 1. If the database name contains escape characters then PSQL unable to connect. 2. If the user terminates the connection by typing the 'exit' command, PSQL will show the connection termination msg. Fixes #2341 Branch --