Updated watchdog readme with write_debug environment variable
@@ -79,6 +79,7 @@ The watchdog can be configured through environmental variables. You must always
| `read_timeout` | HTTP timeout for reading the payload from the client caller (in seconds) |
| `suppress_lock` | The watchdog will attempt to write a lockfile to /tmp/ for swarm healthchecks - set this to true to disable behaviour. |
| `exec_timeout` | Hard timeout for process exec'd for each incoming request (in seconds). Disabled if set to 0. |
+| `write_debug` | Write all output, error messages, and additional information to the logs. Default is false. |
## Advanced / tuning
