Add a developer FAQ

This is a first stab a developer FAQ in our documentation. The only
question answered so far is "How do I create a migration script
template?" because every time I have to google that.

This FAQ should be extended with more answers from questions we get from
day to day.

Change-Id: I3a81261892c359e624ed2dbeb7cd42b11b799a6d

doc/source/dev/faq.rst

@@ -0,0 +1,28 @@
+.. _faq:
+
+==========================================
+Developer FAQ (frequently asked questions)
+==========================================
+
+Here are some answers to frequently-asked questions from IRC and
+elsewhere.
+
+.. contents::
+    :local:
+    :depth: 2
+
+
+How do I…
+=========
+
+…create a migration script template?
+------------------------------------
+
+Using the ``alembic revision`` command, e.g::
+
+  $ cd ironic/ironic/db/sqlalchemy
+  $ alembic revision -m "create foo table"
+
+For more information see the `alembic documentation`_.
+
+.. _`alembic documentation`: https://alembic.readthedocs.org/en/latest/tutorial.html#create-a-migration-script

doc/source/index.rst

@@ -67,6 +67,11 @@ Introduction
   dev/dev-quickstart
   dev/vendor-passthru
 
+.. toctree::
+  :maxdepth: 1
+
+  dev/faq
+
 API References
 --------------