Add changelog (#250)

Author: mrmrcoleman

docs/changelog.md

@@ -0,0 +1,28 @@
+# Changelog
+
+## 0.4.0
+---
+
+### New Features
+
+**Limited Branching Compatibility for Custom Objects**
+
+Custom Objects now has limited compatibility with NetBox Branching. Please see the documentation for more details.
+
+### Enhancements
+
+- [#37](https://github.com/netboxlabs/netbox-custom-objects/issues/37) - Limited Branching compatibility for Custom Objects
+- [#42](https://github.com/netboxlabs/netbox-custom-objects/issues/42) - Populate default values for Multi-Object fields
+- [#87](https://github.com/netboxlabs/netbox-custom-objects/issues/87) - Make Custom Object "name" clickable
+- [#150](https://github.com/netboxlabs/netbox-custom-objects/issues/150) - Cannot import created CustomObject (Documentation)
+
+### Bug Fixes
+
+- [#70](https://github.com/netboxlabs/netbox-custom-objects/issues/70) - Incorrect validation message on integer field min/max defaults
+- [#104](https://github.com/netboxlabs/netbox-custom-objects/issues/104) - Bulk edit not possible on fields of type `object`
+- [#105](https://github.com/netboxlabs/netbox-custom-objects/issues/105) - Bulk edit not possible on fields of type `multiobject`
+- [#172](https://github.com/netboxlabs/netbox-custom-objects/issues/172) - Postgres errors on startup
+- [#189](https://github.com/netboxlabs/netbox-custom-objects/issues/189) - Exceptions when creating Custom Objects
+- [#195](https://github.com/netboxlabs/netbox-custom-objects/issues/195) - RecursionError in netbox_custom_objects plugin due to circular dependencies in CustomObjectType Fields
+- [#210](https://github.com/netboxlabs/netbox-custom-objects/issues/210) - Custom Objects plugin visible when logged out
+- [#212](https://github.com/netboxlabs/netbox-custom-objects/issues/212) - Quick Search not working