CPLAT-12081 Readme Improvements

CHANGELOG.md

@@ -203,10 +203,10 @@ __Analyzer Plugin Changes:__
   the awesome [redux.dart library](https://github.com/johnpryan/redux.dart) to make it easy
   to set up redux provider(s) / consumer(s) for OverReact components that enable granular, targeted updates!
     - Check out [some examples](https://github.com/Workiva/over_react/tree/master/web/over_react_redux)
-      by cloning this project locally, running `webdev serve` from the root of the project, and navigating to <http://localhost:8080/over_react_redux/>.
+      by cloning this project locally, running `webdev serve` from the root of the project, and navigating to `http://localhost:8080/over_react_redux/`.
     - Use it in your project by [upgrading your `UiComponent`s to `UiComponent2`](https://github.com/Workiva/over_react/blob/master/doc/ui_component2_transition.md#updating) and importing `package:over_react/over_react_redux.dart`!
 - We've even got some sweet [redux dev tools you can use](https://github.com/Workiva/over_react/blob/master/doc/over_react_redux_documentation.md#using-redux-devtools) to make the inspection of connected state a breeze!
-  ![over_react_redux.dart developer tools](http://g.recordit.co/NLeAZQkCFm.gif)
+  ![over_react_redux.dart developer tools](https://g.recordit.co/NLeAZQkCFm.gif)
 
 > [__Learn more about using over_react_redux.dart__](https://github.com/Workiva/over_react/blob/master/doc/over_react_redux_documentation.md)
 
@@ -1014,7 +1014,7 @@ __Bug Fixes__
 
 __New Features__
 
-* [#76]: Add support for [`covariant`](http://news.dartlang.org/2017/02/dart-122-faster-tools-assert-messages.html) props / state fields.
+* [#76]: Add support for [`covariant`](https://news.dartlang.org/2017/02/dart-122-faster-tools-assert-messages.html) props / state fields.
   * Closes [#49]
 
 __Bug Fixes__

CONTRIBUTING.md

@@ -45,6 +45,18 @@ thank you!)
    detail as necessary.
 1. See instructions in PR template for getting review on your changes.
 
+## Running Unit Tests Locally
+When running tests in `over_react`, our `dart_test.yaml` specifies some handy presets for running tests in DDC and dart2js:
+
+* To run tests in `over_react` compiled via __DDC__, run:
+    ```bash
+    $ pub run build_runner test -- -P dartdevc
+    ```
+
+* To run tests in `over_react` compiled via __dart2js__, run:
+    ```bash
+    $ pub run build_runner test -r -- -P dart2js
+    ```
 
 ### Coding Standards
 A lot can be gained by writing code in a consistent way. Moreover, always