feat(snipe_it): add ansible role for deployment

roles/snipe_it/README.md

@@ -13,9 +13,9 @@ for sending email. For installing and configuring MariaDB, see
 
 Required variables to set are:
 
-- `snipe_it_domain`
-- `snipe_it_config_app_url`
-- `snipe_it_config_app_key`
+- `snipe_it_domain` - domain name of the snipe-it instance
+- `snipe_it_config_app_url` - URL where snipe-it will be reachable including protocol and port
+- `snipe_it_config_app_key` - Laravel application key
 
 ### Database configuration