Prepare for release v0.3.0 (#7)

* Add changelog
* allow for newer python versions and remove python3.6 support

.github/workflows/python-package.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2

CHANGELOG.md

@@ -0,0 +1,38 @@
+# Changelog
+
+## [v0.3.0](https://github.com/leifdenby/genesis/tree/v0.3.0)
+
+[Full Changelog](https://github.com/leifdenby/genesis/v0.3.0...v0.2.0)
+
+**added features**:
+
+- Extraction of 3D cloud-base state from 2D tracked clouds ([528b36](https://github.com/leifdenby/genesis/commit/5238b3696e4fde336e54e15783e7e657189f9014))
+
+- Extraction of first rise for tracked 2D objects [9465b1a](https://github.com/leifdenby/genesis/commit/9465b1a182a64417fbabcd6dae256c7e6bdc965a)
+
+- KDE-based density of flux decomposition plot [5508a12](https://github.com/leifdenby/genesis/commit/5508a12ef223cc78aadfab9c1e840d5a9d5c1b69)
+
+- General function for 2D binned statistics of xr.DataArrays [f4768f7](https://github.com/leifdenby/genesis/commit/f4768f7c8537ce80632e21a0cdc4c4742cf5469a)
+
+- Cumulant assymmetry on profile plots [8eeace9](https://github.com/leifdenby/genesis/commit/8eeace919965ccee8085525eef874c9980ab55ef)
+
+- isometric rendering of idealised 3D outline shapes [03ae46c](https://github.com/leifdenby/genesis/commit/03ae46c67620ac74bb763c68faf130cca53ef62c)
+
+- cumulants along only one dimension (e.g. for height profiles of horizontal
+  cumulant) [fe4992d](https://github.com/leifdenby/genesis/commit/fe4992d8f3619aa151322473ade734a625f49b1e)
+
+- offset 3D extraction from 2D tracking with Gallilean transform [1210fca](https://github.com/leifdenby/genesis/commit/1210fca44abbae3dd94a336815f0c851b9816b6a)
+
+**bugfixes**:
+
+- Fix annotation marker for cumulant anti-correlation [21a5715](https://github.com/leifdenby/genesis/commit/21a571522bfdebb541d4af17ea54e3288a63e4f6)
+
+**maintenance**:
+
+- Aggregation of properties for projected 2D objects refactored ([c3c8610](https://github.com/leifdenby/genesis/commit/c3c8610c0d504abea9a5aa79779f449a28177322))
+
+
+## [v0.2.0](https://github.com/leifdenby/genesis/tree/v0.2.0)
+
+First release to coincide with publication draft. Contains functionality for
+identifying and characterising 3D coherent structures

environment.yml

@@ -3,7 +3,7 @@ channels:
   - conda-forge
 dependencies:
   - pip=19.0.1
-  - python=3.6
+  - python>=3.7
   - cartopy
   - jupyter
   - matplotlib