Document support for multi-line arguments

Fixes #88

.github/workflows/integTest-action-inputs.yml

@@ -21,5 +21,7 @@ jobs:
         arguments: |
             --configuration-cache
             --build-cache
+            -DsystemProperty=FOO
+            -PgradleProperty=BAR
             test
             jar

README.md

@@ -47,6 +47,7 @@ Each invocation will start its run with the filesystem state remaining from the
 ### Command-line arguments
 
 The `arguments` input can used to pass arbitrary arguments to the `gradle` command line.
+Arguments can be supplied in a single line, or as a multi-line input.
 
 Here are some valid examples:
 ```yaml
@@ -54,8 +55,11 @@ arguments: build
 arguments: check --scan
 arguments: some arbitrary tasks
 arguments: build -PgradleProperty=foo
-arguments: build -DsystemProperty=bar
-....
+arguments: |
+    build
+    --scan
+    -PgradleProperty=foo
+    -DsystemProperty=bar
 ```
 
 See `gradle --help` for more information.

action.yml

@@ -14,7 +14,7 @@ inputs:
     description: Path to the root directory of the build
     required: false
   arguments:
-    description: Gradle command line arguments, see gradle --help
+    description: Gradle command line arguments (supports multi-line input)
     required: false
   cache-disabled:
     description: When 'true', all caching is disabled. No entries will be written to or read from the cache.