support custom fields for timesheets, customers, projects and activities (#871)

src/DependencyInjection/Configuration.php

@@ -83,12 +83,6 @@ class Configuration implements ConfigurationInterface
                 ->end()
                 ->scalarNode('mode')
                     ->defaultValue('default')
-                    ->validate()
-                        ->ifTrue(function ($value) {
-                            return !in_array($value, ['default', 'duration_only', 'punch']);
-                        })
-                        ->thenInvalid('Chosen timesheet mode is invalid, allowed values: default, duration_only, punch')
-                    ->end()
                 ->end()
                 ->booleanNode('markdown_content')
                     ->defaultValue(false)