Update release.schema to work with Dgraph v1.1.1.

[danielmai]

In v1.1.1 setting the release.schema on a live cluster returns this error:

{"errors":[{"message":"Schema does not contain a matching predicate for field apple_movietrailer_id in type Film","extensions":{"code":"Error"}}]}$

All the predicates used as a type field must have a schema entry before it can be used for a type.

• Add schema entries for all predicates
• Remove type declarations for type fields. Note: This makes the schema incompatible with v1.1.0.

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