A good enhancement in Drupal 8 is having list of yml file to import via installation in mymodule_root\config\install, but this means I can not reinstall a module because the configuration settings already exist in the active configuration.
Actually the problem is when uninstalling the module: The imported configuration settings, imported during installation, aren't waived.
Test scenario
Put this sample .yml file in yourmodule_root\config\install\systme.site.yml.
name: 'Admissions at Adelaide'
mail: [email protected]
slogan: ''
page:
403: ''
404: ''
front: caslogin
admin_compact_mode: false
weight_select_max: 100
langcode: en
default_langcode: en