Add Changelog entry about the license change
Optional Result Storage helper module has been separated.
- Improved: [[#75](https://github.com/ethereum/evmc/pull/75)]
Cable upgraded to 0.2.11.
+- Improved: [[#77](https://github.com/ethereum/evmc/pull/77)]
+ The license changed from MIT to Apache 2.0.
## [5.0.0] - 2018-08-10
