Adding PostgreSQL-13beta information in README

Author: haroon-github

README-linux-x64.txt

@@ -1,7 +1,7 @@
 Welcome to Postgres Installer by 2ndQuadrant
 ============================================
 
-Postgres Installer is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11 and 12. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
+Postgres Installer is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11, 12 and 13beta. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
 
 
 Features
@@ -82,7 +82,7 @@ Getting started with PostGIS
 
 PostGIS is a spatial database extender for PostgreSQL object-relational database. It add support for geographic objects allowing location queries to be run in SQL.
 
-NOTE: PostGIS is not supported for PostgreSQL 12 yet
+NOTE: PostGIS is not supported for PostgreSQL 12 and 13beta as yet
 
 Some of the extensions required for PostGIS.
 

README-osx.txt

@@ -1,7 +1,7 @@
 Welcome to Postgres Installer by 2ndQuadrant
 ============================================
 
-Postgres Installer by 2ndquadrant is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11 and 12. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
+Postgres Installer by 2ndquadrant is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11, 12 and 13beta. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
 
 
 Features
@@ -74,7 +74,7 @@ Getting started with PostGIS
 
 PostGIS is a spatial database extender for PostgreSQL object-relational database. It add support for geographic objects allowing location queries to be run in SQL.
 
-NOTE: PostGIS is not supported for PostgreSQL 12 yet
+NOTE: PostGIS is not supported for PostgreSQL 12 and 13beta as yet
 
 Some of the extensions required for PostGIS.
 

README-windows.txt

@@ -1,7 +1,7 @@
 Welcome to Postgres Installer by 2ndQuadrant
 ============================================
 
-Postgres Installer by 2ndquadrant is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11 and 12. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
+Postgres Installer by 2ndquadrant is a GUI based, user-friendly installer for PostgreSQL that is digitally signed and certified by 2ndQuadrant. The installer is currently available for PostgreSQL versions 9.5, 9.6, 10, 11, 12 and 13beta. Postgres Installer has the ability to run in graphical, command line, or quiet installation modes for  Windows, macOS and Linux.
 
 
 Features
@@ -75,7 +75,7 @@ Getting started with PostGIS
 
 PostGIS is a spatial database extender for PostgreSQL object-relational database. It add support for geographic objects allowing location queries to be run in SQL.
 
-NOTE: PostGIS is not supported for PostgreSQL 12 yet
+NOTE: PostGIS is not supported for PostgreSQL 12 and 13beta as yet
 
 Some of the extensions required for PostGIS.