[1.3.0] docs: add rationale

NOTES.md

@@ -1,11 +1,21 @@
 # notes for myself
 
-Handy shortcut to test in CI
+# Development
+
+```
+nvm use
+yarn install
+yarn package
+```
+
+# Test in CI
+
 ```
 git addm
 git cia --no-edit
 yarn package && git addm && git cia --no-edit &&  git push -f
 ```
 
-Push a release:
+# Push a release
+
 yarn package && git addm && git cia --no-edit &&  git tag -a -f -m "CI builds from url" v1.3.0 && git push -f --follow-tags

README.md

@@ -15,20 +15,55 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Setup Babashka
-        uses: turtlequeue/setup-babashka@v1.2.1
+        uses: turtlequeue/setup-babashka@v1.3.0
         with:
-          babashka-version: 0.3.0
+          babashka-version: 0.3.2
 
       - name: Check bb runs
         run: bb --version
 ```
 
-# Development
+# Rationale
 
+You may be using this already:
+``` shell
+$ bash < <(curl -s https://raw.githubusercontent.com/babashka/babashka/master/install)
 ```
-nvm use
-yarn install
-yarn package
+
+That's great! And this is what this action uses under the hood.
+
+However this action is useful still for:
+
+- supporting more platforms (windows)
+- pinning the babashka version
+- using the github api to cache between runs
+- (advanced) using a CI build by specifying a `babashka-url` (see below)
+
+
+# Use a CI version
+
+You probably don't want to do that.
+But if you do note that:
+- the CI builds from babashka will expire
+- the platform detection is up to you
+
+```yaml
+name: install babashka
+
+on: [push]
+
+jobs:
+  simple:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Setup Babashka
+        uses: turtlequeue/setup-babashka@v1.3.0
+        with:
+          babashka-version: 0.3.3-SNAPSHOT
+          babashka-url: https://16800-201467090-gh.circle-artifacts.com/0/release/babashka-0.3.3-SNAPSHOT-linux-amd64.tar.gz
+
+      - name: Check bb runs
+        run: bb --version
 ```
 
 # License