clarify

README.md

@@ -58,6 +58,29 @@ Greenlock.create({
 ```
 </details>
 
+<details><summary>PostgreSQL, SQL Server, and lesser databases...</summary>
+
+The general format of a DATABASE_URL is something like this:
+
+> `schema://user:pass@server:port/service?option=foo`
+
+For example:
+
+> `postgres://aj:secret123@127.0.0.1:5432/greenlock`
+
+For each database the exact format may be slightly different:
+
+* `postgres://user:pass@hostname:port/database?option=foo`
+* `sqlserver://user:pass@datasource:port/instance/catalog?database=dbname`
+* `mssql://user:pass@hostname:port/database?option=foo`
+* `mysql://user:pass@hostname:port/database?option=foo`
+* `mariadb://user:pass@hostname:port/database?option=foo`
+
+There's also a way to specify objects instead of using the standard connection strings.
+
+See the next section for more information.
+</details>
+
 <details><summary>Database URLs / Connection Strings</summary>
 You may use database URLs (also known as 'connection strings') to initialize sequelize:
 
@@ -82,7 +105,8 @@ Greenlock.create({
 });
 ```
 
-For more information, see the [Sequelize Getting Started](http://docs.sequelizejs.com/manual/getting-started.html) docs.
+See the [Sequelize Getting Started](http://docs.sequelizejs.com/manual/getting-started.html) docs for more info
+on database options for sequelize.
 </details>
 
 <details><summary>Environment variables (AWS, Docker, Heroku, Akkeris)</summary>