CHANGELOG updated

docs/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 - **0.6.0 WIP**
   - linear_algebra updated to 0.7.0/testing
+  - Added angle as SI base dimension (thanks [@kwikius](https://github.com/kwikius))
+  - Added STL random number distribution wrappers (thanks [@yasamoka](https://github.com/yasamoka))
+  - `math.h` function signatures refactored to use a `Quantity` concept (thanks [@kwikius](https://github.com/kwikius))
 
 - **0.5.0 May 17, 2020**
   - Major refactoring and rewrite of the library