Add initial role for Dendrite as alternative Matrix server

roles/matrix-dendrite/tasks/setup_dendrite.yml

@@ -0,0 +1,19 @@
+---
+- name: Ensure Dendrite paths exist
+  file:
+    path: "{{ item.path }}"
+    state: directory
+    mode: 0750
+    owner: "{{ matrix_user_username }}"
+    group: "{{ matrix_user_groupname }}"
+  with_items:
+    - { path: "{{ matrix_dendrite_config_dir_path }}", when: true }
+    - { path: "{{ matrix_dendrite_ext_path }}", when: true }
+    # We handle matrix_dendrite_media_store_path elsewhere (in ./dendrite/setup_install.yml),
+    # because if it's using Goofys and it's already mounted (from before),
+    # trying to chown/chmod it here will cause trouble.
+  when: "(matrix_dendrite_enabled|bool or matrix_s3_media_store_enabled|bool) and item.when"
+
+- import_tasks: "{{ role_path }}/tasks/dendrite/setup.yml"
+
+- import_tasks: "{{ role_path }}/tasks/goofys/setup.yml"