Add basic doc on making dep changes based on previously written one

Author: Jackenmen

source/dependency-changes.rst

@@ -0,0 +1,13 @@
+Making dependency changes
+=========================
+
+Updating Python package dependencies
+------------------------------------
+
+To update all dependencies, script for bumping deps (``tools/bumpdeps.py``) should be used.
+
+When updating dependencies:
+
+- Verify that all code commented with ``DEP-WARN`` is not affected by the new dependency versions
+- Read the changelogs for dependencies to make sure there are no (breaking) changes
+  that may affect our code

source/index.rst

@@ -9,3 +9,5 @@ Full Table of Contents
 
 .. toctree::
    :maxdepth: 2
+
+   dependency-changes