[bug] correct the docs 'getting-started'

[lendormi]

update the doc on 'getting-started' because we have this 👍
[critical] Type "Thing" cannot be found.
[critical] Type "Person" cannot be found.
[critical] Type "PostalAddress" cannot be found.

we need schema.rdfa and v1.owl.

[dunglas]

@lendormi this is because the current "prod" version of Schema.org RDFa is broken. This is fixed in master. Maybe can we just wait that the Schema.org team release a new version of the vocabulary?

[lendormi]

As you wish. It's just when i (a newbie on composer) clone the repository and update it.
The command "bin/schema generate-files output-directory address-book" doesn't work. And i lost few hours to understand where the problem comes from.

Perhaps add temporarly a little note on this subjet on README.md

[dunglas]

You're right. I'll revert this commit when it the Schema.org file will be fixed.