pg: improve pg README.md (#15206)

Author: enghitalo

vlib/pg/README.md

@@ -1,13 +1,13 @@
 ## Description:
 
-`pg` is a wrapper for the PostgreSQL client library. It provides access
-to a PostgreSQL DB server.
+`pg` is a wrapper for the PostgreSQL client library. It provides access to a PostgreSQL
+database server.
 
-Before you can use this module, you must first have PostgreSQL installed on
-your system. To do this, find your OS and perform the actions listed.
+Before you can use this module, you must first have PostgreSQL installed on your system.
+To do this, find your OS and perform the actions listed.
 
-**NOTE**: These instructions are meant only as a convenience. If your OS is not
-listed or you need extra help, [go here](https://www.postgresql.org/download/).
+**NOTE**: These instructions are meant only as a convenience. If your OS is not listed 
+or you need extra help, [go here](https://www.postgresql.org/download/).
 
 ### Fedora 31
 ```
@@ -16,7 +16,7 @@ sudo systemctl enable postgresql # to autostart on startup
 sudo systemctl start  postgresql
 ```
 
-### Debian 10/11
+### Ubuntu/Debian
 ```
 sudo apt-get install postgresql postgresql-client
 sudo systemctl enable postgresql # to autostart on startup
@@ -28,3 +28,25 @@ sudo systemctl start  postgresql
 brew install postgresql
 brew services start postgresql
 ```
+
+### MacOSX (MacPorts)
+```
+gem install pg -- --with-pg-config=/opt/local/lib/postgresql[version number]/bin/pg_config
+```
+
+## Installing libpq-dev or its equivalent for your OS: ##
+
+**Ubuntu/Debian**: `sudo apt-get install libpq-dev`
+
+**Red Hat Linux (RHEL)**: `yum install postgresql-devel`
+
+**OpenSuse**: `zypper in postgresql-devel`
+
+**ArchLinux**: `pacman -S postgresql-libs`
+
+##Getting Started with [PostgreSQL](https://www.postgresqltutorial.com/postgresql-getting-started)
+
+Read this section to learn how to install and connect to PostgreSQL
+*[Windows](https://www.postgresqltutorial.com/install-postgresql)*;
+*[Linux](https://www.postgresqltutorial.com/postgresql-getting-started/install-postgresql-linux)*;
+*[macOS](https://www.postgresqltutorial.com/postgresql-getting-started/install-postgresql-macos)*.