v0.7.2

• graphql-js parity v0.6.0.
• go-fuzz nil panic fixes @ https://github.com/graphql-go/graphql/pull/223 https://github.com/graphql-go/graphql/pull/224
• sort fields by name for better reading on introspection @ https://github.com/graphql-go/graphql/pull/225
• fixes for input object default values @ https://github.com/graphql-go/graphql/pull/226
• exposes default resolve function outside the lib @ https://github.com/graphql-go/graphql/pull/227
• empty string improvements @ https://github.com/graphql-go/graphql/pull/228
• cyclic fields support @ https://github.com/graphql-go/graphql/pull/229