Use local ansible.cfg

Since moving playbooks to their own subdirectory they were no longer
able to find the roles. Add a local `ansible.cfg` which configures the
default paths for roles, modules, and collections. Also change the
location of the `win_git` module to the new local directory.

.gitignore

@@ -1 +1,2 @@
 external
+modules/win_git*

ansible.cfg

@@ -0,0 +1,5 @@
+[defaults]
+collections_path = collections
+library = modules
+roles_path = roles
+stdout_callback = yaml

roles/wsl/tasks/main.yaml

@@ -36,7 +36,7 @@
 - name: copy win_git files to ansible modules directory
   copy:
     src: '~/.config/local/external/ansible-win_git/{{item}}'
-    dest: '~/.ansible/plugins/modules/{{item}}'
+    dest: '~/.config/local/modules/{{item}}'
   with_items:
     - win_git.ps1
     - win_git.py