Add something in the cookbook.

Author: ionelmc

docs/cookbook.rst

@@ -2,4 +2,58 @@
 Cookbook
 ========
 
-TODO
+.. epigraph::
+
+    When in doubt, use hunter.
+
+Packaging
+=========
+
+I frequently use Hunter to figure out how distutils/setuptools work. It's very hard to figure out what's going on by just
+looking at the code - lots of stuff happens at runtime. If you ever tried to write a custom command you know what I mean.
+
+To show everything that is being run::
+
+    PYTHONHUNTER='module_startswith=["setuptools", "distutils", "wheel"]' python setup.py bdist_wheel
+
+If you want too see some interesting variables::
+
+    PYTHONHUNTER='module_startswith=["setuptools", "distutils", "wheel"], actions=[CodePrinter, VarsPrinter("self.bdist_dir")]' python setup.py bdist_wheel
+
+Typical
+=======
+
+Normally you'd only want to look at your code. For that purpose, there's the ``stdlib`` option. Set it to ``False``.
+
+Building a bit on the previous example, if I have a ``build`` Distutils command and I only want to see my code then I'd run
+this::
+
+    PYTHONHUNTER='stdlib=False' python setup.py build
+
+But this also means I'd be seeing anything from ``site-packages``. I could filter on only the events from the current
+directory (assuming the filename is going to be a relative path)::
+
+    PYTHONHUNTER='~Q(filename_startswith="/")' python setup.py build
+
+Needle in the haystack
+======================
+
+If the needle might be though the stdlib then you got not choice. But some of the `hay` is very verbose and useless, like
+stuff from the ``re`` module.
+
+Note that there are few "hidden" modules like ``sre``, ``sre_parse``, ``sre_compile`` etc. You can filter that out with::
+
+    PYTHONHUNTER='~Q(module_regex="(re|sre.*)$")'
+
+Although filtering out that regex stuff can cut down lots of useless output you usually still get lots of output.
+
+Another way, if you got at least some vague idea of what might be going on is to "grep" for sourcecode. Example, to show all
+the code that does something with a ``build_dir`` property::
+
+    PYTHONHUNTER='source_contains=".build_dir"'
+
+You could even extend that a bit to dump some variables::
+
+    PYTHONHUNTER='source_contains=".build_dir", actions=[CodePrinter, VarsPrinter("self.build_dir")]'
+
+