Update readme

README.md

@@ -22,6 +22,7 @@ application to work with local or remote PostgreSQL databases.
 - Zero dependencies
 - Simple installation (distributes as a single binary)
 - Connect to local or remote servers
+- Multiple database sessions
 - Browse tables and table rows
 - Get table details: structure, size, indeces, row count
 - Run and analyze custom SQL queries
@@ -31,6 +32,10 @@ application to work with local or remote PostgreSQL databases.
 
 Visit [WIKI](https://github.com/sosedoff/pgweb/wiki) for more details
 
+## Demo
+
+Visit https://pgweb-demo.herokuapp.com to see pgweb in action.
+
 ## Installation
 
 [Precompiled binaries](https://github.com/sosedoff/pgweb/releases) for supported 
@@ -58,6 +63,20 @@ Connection URL scheme is also supported:
 pgweb --url postgres://user:password@host:port/database?sslmode=[mode]
 ```
 
+### Multiple database sessions
+
+To enable multiple database sessions in pgweb, start the server with:
+
+```
+pgweb --sessions
+```
+
+Or set environment variable:
+
+```
+SESSIONS=1 pgweb
+```
+
 ## Deploy on Heroku
 
 [![Heroku Deploy](https://www.herokucdn.com/deploy/button.png)](https://heroku.com/deploy?template=https://github.com/sosedoff/pgweb)