Add updated posgres url information (#731)

* Add additional posgres url information

* Added some ssl examples

* Use coding block

* More spacing

* nit

Co-authored-by: Tom Fox <[email protected]>

Author: cbaker6

_includes/parse-server/database.md

@@ -28,10 +28,24 @@ The Postgres requirements for Parse Server are:
 * Postgres version 9.5
 * PostGIS extensions 2.3
 
-The postgres database adapter will be automatically loaded when you pass a valid postgres URL, for example: `postgres://localhost:5432`.
+The postgres database adapter will be automatically loaded when you pass a valid postgres URL, for example: `postgres://localhost:5432`. The available configuration options through the URL are: 
+
+```
+postgres://localhost:5432/db?ssl=boolean&rejectUnauthorized=boolean&ca=/path/to/file&pfx=/path/to/file&cert=/path/to/file&key=/path/to/file&passphrase=string&secureOptions=number&client_encoding=string&application_name=string&fallback_application_name=string&max=number&query_timeout=idleTimeoutMillis=number&poolSize=number&binary=boolean&keepAlive=boolean
+``` 
+
+Details about the configuration options can be found on [pg-promise](https://github.com/vitaly-t/pg-promise/wiki/Connection-Syntax). Some useful combinations are below:
+
+* SSL with verification - `postgres://localhost:5432/db?ca=/path/to/file` 
+* SSL with no verification - `postgres://localhost:5432/db?ssl=true&rejectUnauthorized=false`
 
 ### Caveats
 
 * Join tables are resolved in memory, there is no performance improvements using Postgres over MongoDB for relations or pointers.
 * Mutating the schema implies running ALTER TABLE, therefore we recommend you setup your schema when your tables are not full.
 * Properly index your tables to maximize the performance.
+* The postgres URL for 4.2.0 and below only supports the following configuration options:
+
+    ```
+    postgres://localhost:5432/db?ssl=boolean&client_encoding=string&application_name=string&fallback_application_name=string&poolSize=number&binary=boolean&keepAlive=boolean
+    ```