Add CHANGELOG.md (#69)

CHANGELOG.md

@@ -0,0 +1,38 @@
+# Changelog
+
+## Unreleased
+
+TBD
+
+## [v1.3.1](https://github.com/medibloc/panacea-core/releases/tag/v1.3.1) - 2020-10-19
+
+### Features
+
+- [\#68](https://github.com/medibloc/panacea-core/pull/68) Enhance the `x/aol` message validation
+- [\#58](https://github.com/medibloc/panacea-core/pull/58) Upgrade `medibloc/cosmos-sdk` from [v0.35.6-internal](https://github.com/medibloc/cosmos-sdk/releases/tag/v0.35.6-internal) to [v0.37.15](https://github.com/medibloc/cosmos-sdk/releases/tag/v0.37.15).
+- [\#66](https://github.com/medibloc/panacea-core/pull/66) Integrate with Gitbook
+
+### Bug fixes
+
+- [\#67](https://github.com/medibloc/panacea-core/pull/67) Use `documents` as the `x/did` genesis JSON key, instead of `Documents`.
+
+
+## [v1.3.0-internal](https://github.com/medibloc/panacea-core/releases/tag/v1.3.0-internal) - 2020-09-29
+
+### Features
+
+- [\#7](https://github.com/medibloc/panacea-core/pull/7) ~ [\#49](https://github.com/medibloc/panacea-core/pull/49), [\#57](https://github.com/medibloc/panacea-core/pull/57) Support DID operations
+
+### Bug fixes
+
+- [\#59](https://github.com/medibloc/panacea-core/pull/59) Fix failed gentx because node is untrusted
+    - This bug will be resolved after upgrading cosmos-sdk to [v0.37.11+](https://github.com/cosmos/cosmos-sdk/pull/6021).
+
+
+## [v1.2.6-internal](https://github.com/medibloc/panacea-core/releases/tag/v1.2.6-internal) - 2020-10-14
+
+### Features
+
+- [\#63](https://github.com/medibloc/panacea-core/pull/63) Add a new option: `halt-height` and Upgrade `medibloc/cosmos-sdk` to [v0.35.7-internal](https://github.com/medibloc/cosmos-sdk/releases/tag/v0.35.7-internal).
+    - This feature will be introduced from the cosmos-sdk [v0.36.0](https://github.com/cosmos/cosmos-sdk/pull/4059).
+