The ErrorType enum should be removed

I think the graphql.ErrorType enum can be removed, and along with it GraphQLError#gerErrorType(). I think these add needless complexity and are not part of the spec.

The only specified error properties are are

Every error must contain an entry with the key message with a string description of the error intended for the developer as a guide to understand and correct the error.

If an error can be associated to a particular point in the requested GraphQL document, it should contain an entry with the key locations with a list of locations, where each location is a map with the keys line and column, both positive numbers starting from 1 which describe the beginning of an associated syntax element.

[bbakerman]

This is a breaking change however. Anyone consuming this in their error handling be broken.

Semver says this must be a 3.x change

[andimarek]

we will not remove the ErrorType: I think it is quite useful and as @tklovett pointed out it is spec conform.