The great refactor (#82)

source/templates/community/README.md

@@ -0,0 +1,25 @@
+### 📕 Community templates
+
+It is possible to use official releases with templates from forked repositories (whether you own them or not).
+
+Use `setup_community_templates` option to specify additional external sources using following format: `user/repo@branch:template`.
+Templates added this way will be downloaded through git and can be used by prefixing their name with an `@`.
+
+By default, community templates use `template.mjs` from official `classic` template instead of their own, to prevent executing malicious code and avoid token leaks.
+
+If you trust it, append `+trust` after their name.
+
+```yaml
+- uses: lowlighter/metrics@master
+  with:
+    # ... other options
+    template: "@super-metrics"
+    # Download "super-metrics" and "trusted-metrics" templates from "octocat/metrics@master"
+    # "@trusted-metrics" template can execute remote JavaScript code
+    setup_community_templates: octocat/metrics@master:super-metrics, octocat/metrics@master:trusted-metrics+trust
+```
+
+To create a new community template, fork this repository and create a new folder in `/source/templates` with same structure as current templates.
+Then, it's just as simple as HTML and CSS with a bit of JavaScript!
+
+If you made something awesome, please share it here!