Missing type declarations for components
I was using Fabric.js and stumbeled upon your framework, I was rebuilding a lot of components and functionality that react-sketch allready contains. What I noticed is that when I run `npm i @types/react-sketch` npm cannot find a type declaration file. I added it by hand, I used the one in the types folder on the master branch and noticed that it only contained a declaration file for `SketchField` and not the other components. 

Do you have a complete declaration file or should I make one? 

List of components to add are: 

- Arrow 
- Circle 
- fabrictool
- history 
- line 
- pan
- pencil 
- rectangle
- select
