v14.0.0-rc.1

NOTE
This is a pre-release. There is a high likelihood there will be more breaking changes introduced prior to the 14.0.0 release.

Breaking:

• Drops support for node v4, makes sure node v10 is supported (#1338)
• Reject invalid scalar value coercion (#1365, #1336)
• Removes VariablesDefaultValueAllowed validation rule, and ProvidedNonNullArguments became ProvidedRequiredArguments (#1274)
• Requires Interfaces to have at least on implementing Object

New:

• Parse new schema extensions (#1314, #1323)
• Export SDL AST types (#1315)
• extendSchema extended with spec-compliant SDL extensions (#1373)
• symbol.toStringTag support (#1297)
• Expose getOperationRootType(schema, operationAST) (#1345)
• Package is marked as side-effect free (#1312)

Fixed:

• Fixes for custom enum types
• Prettier, Flow and eslint upgrades (#1304, #1319)
• Babel 7 upgrade (#1350)
• Introspection query perf improved (#1329)