Add details for v1 and v2

README.md

@@ -10,8 +10,6 @@ CardKit has three main parts:
 
 Additionally, a base class allows you to create your own renderers. See more in the [Custom Renderers](#custom-renderers) section.
 
-**For version 1, see the [`v1-master`](https://github.com/chrishutchinson/cardkit/tree/v1-master) branch**
-
 ## Installation
 
 `$ npm install cardkit --save`
@@ -22,6 +20,12 @@ CardKit requires a configuration object in order to render an image. Each render
 
 In addition to these, you may also want to try the [CardKit Yeoman Generator](https://www.github.com/times/generator-cardkit), which can help you scaffold an entire project in just a few moments. It brings with it the latest version of CardKit, a recommended directory structure, and a build process that helps you get your CardKit project deployed. There is also a [JSFiddle](https://jsfiddle.net/chrishutchinson/16tLs2ta/) that you can fork and edit for quick in-browser testing without touching the command line.
 
+### Previous versions
+
+For **version 1**, see the [`v1-main`](https://github.com/chrishutchinson/cardkit/tree/v1-main) branch.
+
+For **version 2**, see the [`v2-main`](https://github.com/chrishutchinson/cardkit/tree/v2-main) branch.
+
 #### Yeoman generator
 
     $ npm install -g yo generator-cardkit