Adds ansible playbook for foundry setup

Currently, running the playbook will:
- Install dependencies (Caddy, nodejs, unzip)
- Create a foundry user
- Extract foundry app into folder on server
- Update Caddyfile with reverse proxt config

TODO:
- unit file for foundry itself
- data directory

.gitignore

@@ -0,0 +1,5 @@
+# Don't check in the foundry app itself
+foundryvtt.zip
+
+# Or the variables file
+variables.yml