Add wsl role to when WSL is detected in kernel name

This role sets up the non-standard `win_git:` module for use when
managing a Windows host from within WSL on the same system.

.gitignore

@@ -0,0 +1 @@
+external

main.yaml

@@ -6,6 +6,8 @@
     - role: neovim
     - role: git
     - role: python
+    - role: wsl
+      when: '"WSL" in ansible_kernel'
 
 - hosts: windows
   roles:

roles/wsl/tasks/main.yaml

@@ -0,0 +1,21 @@
+---
+- name: create external directory
+  file:
+    dest: external
+    state: directory
+- name: clone ansible win_git module
+  git:
+    repo: https://github.com/tivrobo/ansible-win_git.git
+    dest: external/ansible-win_git
+    version: master
+- name: create ansible modules directory
+  file:
+    dest: ~/.ansible/plugins/modules
+    state: directory
+- name: copy win_git files to ansible modules directory
+  copy:
+    src: '~/.config/local/external/ansible-win_git/{{item}}'
+    dest: '~/.ansible/plugins/modules/{{item}}'
+  with_items:
+    - win_git.ps1
+    - win_git.py