Update CHANGES

Author: rrosenzweig

CHANGES.md

@@ -1,7 +1,13 @@
-Unreleased
+0.7.0 2018-08-10
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+- Allow returning errors from resolve function of io_field (#69)
+- Support for union and interface types (#70)
 - Expose HTTP request to context construction function in Graphql_lwt.Server.start (#88)
+- Fix error response from Graphql_lwt.Server (#96)
+- Allow passing operation name to Graphql_lwt.Server (#103)
+- Querying undefined fields gives validation error (#105)
+- Fix parsing of enums with E (#109)
 
 0.6.0 2018-03-31
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