[autohelp] display information on import error

When a module import fails the wrapper script doesn't display its
path/name, so it is complicated to debug. this patch displays the module
name before re-raising the exception.

Change-Id: Ie9d691a41b0c178b856f19605a8c6434d3ce2c88

autogenerate_config_docs/autohelp.py

@@ -107,6 +107,10 @@ def import_modules(repo_location, package_name, verbose=0):
                     if verbose >= 2:
                         print(e)
                     continue
+                except Exception as e:
+                    print("Impossible to import module %s" % modname)
+                    raise e
+
                 _register_runtime_opts(module, abs_path, verbose)
                 _run_hook(modname)