improve services

_config.yml

_data/nav.yml

_layer2/_defaults.md

_layer2/engine.md

_quickstart/choose_library.md

_services/dhf.md

_services/ecency.com.md

_services/hive.blog.md

_services/hivesigner.md

_services/imageHoster.md

_services/jussi.md

_services/videoHoster.md

layer2.html