Update readmes in test-playbook-* dirs

Author: serpro69

test-playbook-git-source/README.md

@@ -1,6 +1,10 @@
-# test-playbook-local-source
+# test-playbook-git-source
 
-Runs the `helloworld` module from the collection which is installed from the local directory source.
+Runs the `helloworld` module from the collection which is installed from the remote git repository.
+
+## Requirements
+
+* none
 
 ## Usage
 

test-playbook-local-library/README.md

@@ -1,6 +1,6 @@
-# test-playbook-local-source
+# test-playbook-local-library
 
-Downloads the `helloworld` module binary and runs it from the playbook.
+Runs the `helloworld` module which downloaded from remote location.
 
 ## Usage
 

test-playbook-local-source/README.md

@@ -2,6 +2,10 @@
 
 Runs the `helloworld` module from the collection which is installed from the local directory source.
 
+## Requirements
+
+* none
+
 ## Usage
 
 ```

test-playbook-role-helper/README.md

@@ -1,6 +1,11 @@
-# test-playbook-local-source
+# test-playbook-role-helper
 
-Runs the `helloworld` module from the collection which is installed from the local directory source.
+Runs the `helloworld` module which is installed by a "helper" role which is distributed as part of the collection.
+
+## Requirements
+
+* Go must be installed on the ansible controller
+  * The role checks for the presence of `go` executable by running `go version`
 
 ## Usage