Add support for Synapse Simple Antispam

Fixes #255 (Github Issue).

roles/matrix-synapse/tasks/ext/synapse-simple-antispam/setup_install.yml

@@ -0,0 +1,41 @@
+---
+
+- name: Fail if Synapse Simple Antispam blocked homeservers is not set
+  fail:
+    msg: "Synapse Simple Antispam is enabled, but no blocked homeservers have been set in matrix_synapse_ext_spam_checker_synapse_simple_antispam_config_blocked_homeservers"
+  when: "matrix_synapse_ext_spam_checker_synapse_simple_antispam_config_blocked_homeservers|length == 0"
+
+- name: Ensure git installed (RedHat)
+  yum:
+    name:
+      - git
+    state: present
+    update_cache: no
+  when: "ansible_os_family == 'RedHat'"
+
+- name: Ensure git installed (Debian)
+  apt:
+    name:
+      - openssl
+    state: present
+    update_cache: no
+  when: "ansible_os_family == 'Debian'"
+
+- name: Clone synapse-simple-antispam git repository
+  git:
+    repo: "{{ matrix_synapse_ext_spam_checker_synapse_simple_antispam_git_repository_url }}"
+    version: "{{ matrix_synapse_ext_spam_checker_synapse_simple_antispam_git_version }}"
+    dest: "{{ matrix_synapse_ext_path }}/synapse-simple-antispam"
+  become: true
+  become_user: "{{ matrix_user_username }}"
+
+- set_fact:
+    matrix_synapse_spam_checker:
+      module: "synapse_simple_antispam.AntiSpamInvites"
+      config:
+        blocked_homeservers: "{{ matrix_synapse_ext_spam_checker_synapse_simple_antispam_config_blocked_homeservers }}"
+
+    matrix_synapse_container_extra_arguments: >
+      {{ matrix_synapse_container_extra_arguments|default([]) }}
+      +
+      {{ ["--mount type=bind,src={{ matrix_synapse_ext_path }}/synapse-simple-antispam/synapse_simple_antispam,dst={{ matrix_synapse_in_container_python_packages_path }}/synapse_simple_antispam,ro"] }}