[lib,showcase][xs]: use inlined readme if already present on the datapackage.json.
[lib,showcase][xs]: use inlined readme if already present on the datapackage.json.

This solves the issue we are having that pipeline can't handle README.md (basically cli inlines on datapackage.json and frontend pulls back out).

See also https://github.com/datahq/datahub-cli/issues/110.

datahq/frontend,datahq/frontend