Readme updates (#2)

* Update README.md

* add contributing, license, readme updates

* cleanup

* Update README.md

README.md

@@ -1,52 +1,19 @@
 
 # GitHub First Party Actions Cache
 
-This repository builds the layout for first party actions cache.
+This repository contains the code and scripts responsible for caching actions locally on a GitHub [Actions Runner](https://github.com/actions/runner).
+
+This allows you to speedup actions execution without the cost of downloading actions during the course of your job during the `Setup Job` step. This repository only caches the most popular first party actions, to save disk space.
 
 A configuration file exists for each repository (see `config/actions/`). The refs are pinned to specific commit SHAs.
 
-## Build
-
-To build the layout, run `script/build.sh`
-
-## Actions
-
-### Add an action
-
-To add an action, run `script/add-action.sh`
-
-__Example adding an action__
-
-```
-script/add-action.sh actions/checkout
-```
-
 ### Which refs are included?
 
-By default only `master` and version tags are included. For example: `v1` or `v2.0.1`
+By default only `main` and version tags are included. For example: `v1` or `v2.0.1`
 
 Preview versions are intentionally excluded. For example: `v2-beta`
 
 Optional args may be supplied to control which refs are included. See `script/add-action.sh --help` for more info.
 
-### Update an action
-
-To update the refs for an action, run `script/update-action.sh`
-
-__Example updating one action__
-
-```
-script/update-action.sh actions/checkout
-```
-
-__Example updating all actions__
-
-```
-script/update-action.sh --all
-```
-
-- If you hand-edit an action config, make sure you run `script/build.sh` to regenerate the action build scripts.
-
-## Troubleshooting
-
-Set `GITHUB_ACTIONS_DEBUG=1` for debug output
+### Contributing
+See the [contribution guide](../github/CONTRIBUTING.MD). Currently we are not taking requests for non first party actions to be added at this time.