Add "contributing" section

Author: jgoel

README.md

@@ -60,6 +60,19 @@ func main() {
 
 ![](/static/original.jpg)
 
+## Contributing
+
+1. If you want to make any other modification or refactor: please create an
+   issue and talk to me prior to making your PR. This way we can talk about the
+   feature, approach, and my own ability to commit to reviewing and merging code.
+
+2. I don't guarantee that I will keep this repo up to date, or that I will respond
+   in any sort of timely fashion! Your best bet for any change is to keep PRs small
+   and focused on the minimum changeset to add your feature.
+
+3. Of course, you are welcome to fork, modify, and distribute this code with your
+   changes in accordance with the LICENSE.
+
 ## Acknowledgements
 
 - https://plasma.ninja/blog/devices/remarkable/binary/format/2017/12/26/reMarkable-lines-file-format.html