fix: add docs, tests; tweak some handler method signatures

docs/narr/install.rst

@@ -0,0 +1,32 @@
+
+Installation
+============
+
+This assumes you already have a :doc:`WuttJamaican app
+<wuttjamaican:narr/install/index>` setup and working.
+
+Install the Wutta-COREPOS package to your virtual environment:
+
+.. code-block:: sh
+
+   pip install Wutta-COREPOS
+
+Edit your :term:`config file` to add CORE-POS DB connection info, and
+related settings.  Note that so far, only CORE Office DB connections
+are supported.
+
+.. code-block:: ini
+
+   [corepos]
+   office.url = http://localhost/fannie/
+
+   [corepos.db.office_op]
+   default.url = mysql+mysqlconnector://localhost/core_op
+
+   [corepos.db.office_trans]
+   default.url = mysql+mysqlconnector://localhost/core_trans
+
+   [corepos.db.office_arch]
+   default.url = mysql+mysqlconnector://localhost/trans_archive
+
+And that's it, the CORE-POS integration is configured.