Only show stderr_lines by default

This avoids dumping all the parameters which can cause rather lengthy
output if multiple interfaces, routers, ... are configured.
The previous behaviour where all the params etc were displayed can
still be achieved by adding `-v` to the `ansible-playbook` command.

Resolves: #394

Signed-off-by: Kristof Wevers <kristof.wevers@infura.eu>

tasks/main.yml

@@ -87,8 +87,14 @@
     __debug_flags: "{{ __network_debug_flags | default(omit) }}"
   register: __network_connections_result
 
+- name: Show stderr messages
+  debug:
+    var: __network_connections_result.stderr_lines
+
 - name: Show debug messages
-  debug: var=__network_connections_result
+  debug:
+    var: __network_connections_result
+    verbosity: 1
 
 - name: Re-test connectivity
   ping: