FAQ section (#486)

FAQ.md

@@ -0,0 +1,17 @@
+The Sequelize Command Line Interface (CLI) Frequently Asked Question
+
+## How can I generate a model?
+Specify model name with `--name` argument. List of table fields can be passed with `--attributes` option
+``` 
+$ sequelize model:create --name User --attributes name:string,state:boolean,birth:date,card:integer
+```
+
+## What is the command to executes all migrations?
+```
+sequelize db:migrate
+```
+## How can I make a migrations rollback?
+
+```
+sequelize db:migrate:undo:all
+```

README.md

@@ -325,3 +325,7 @@ Additional note: If you need to access the sequelize instance, you can easily do
 ## Help
 
 Read the manuals via `sequelize help:<task-name>` for further information.
+
+## FAQ
+
+You can find FAQ section [here](https://github.com/sequelize/cli/blob/master/FAQ.md)