Edit readme, add change log

Signed-off-by: Vartan Benohanian <vartanbeno@gmail.com>

README.md

@@ -36,6 +36,8 @@ Or for the latest version:
 go get github.com/vartanbeno/go-reddit
 ```
 
+The repository structure for managing multiple major versions follows the one outlined [here](https://github.com/go-modules-by-example/index/tree/master/016_major_version_repo_strategy#major-branch-strategy).
+
 ## Usage
 
 Make sure to have a Reddit app with a valid client id and secret. [Here](https://github.com/reddit-archive/reddit/wiki/OAuth2-Quick-Start-Example#first-steps) is a quick guide on how to create an app and get credentials.

reddit/CHANGELOG.md

@@ -0,0 +1,15 @@
+# Change Log
+
+## [v2.0.0] - 2021-01-24
+
+- The underlying `*http.Client` is now passed as an option when initializing a client.
+- Add `DefaultClient()` method which returns a valid, read-only client with limited access to the Reddit API.
+- Remove the `before` anchor from responses.
+- The decoding process for a listing response has been revamped, and the `after` anchor is now included in the `*Response` object. For example, when fetching a user's comments, instead of getting a struct containing the list of comments, and the `after` value, you now get the list of comments directly, and the `after` can be obtained from the `*Response`.
+- Create `WikiService`, `LiveThreadService`, and `WidgetService`.
+- Add more methods to `SubredditService`, `ModerationService`, and `FlairService`.
+- Add error handling for rate limit errors (`*RateLimitError`).
+
+## [v1.0.0] - 2020-08-25
+
+- Most endpoints outlined in the [official Reddit API documentation](https://www.reddit.com/dev/api/) have been implemented!