Update minimum pyzstd, add zenodo and pre-release environments

Author: effigies

tox.ini

@@ -32,13 +32,13 @@ deps =
   min: pillow ==8.1
   min: h5py ==3.0
   min: indexed_gzip ==1.4
-  min: pyzstd ==0.13
+  min: pyzstd ==0.14.3
   full,pre: scipy >=1.6
   full,pre: matplotlib >=3.4
   full,pre: pillow >=8.1
   full,pre: h5py >=3.0
   full,pre: indexed_gzip >=1.4
-  full,pre: pyzstd >=0.13
+  full,pre: pyzstd >=0.14.3
   min: pydicom ==2.1
   full: pydicom >=2.1
   pre: pydicom @ git+https://github.com/pydicom/pydicom.git@master
@@ -130,3 +130,15 @@ deps =
 skip_install = true
 commands =
   python -m twine upload dist/*
+
+[testenv:zenodo]
+deps = gitpython
+skip_install = true
+commands =
+  python tools/prep_zenodo.py
+
+[testenv:pre-release]
+depends =
+  zenodo
+  style-fix
+  build