Add trigger developer doc
Move developer docs to their own subdir (to avoid filename conflicts
with current doc set), and add a (very basic) new dev doc for triggers.
Change-Id: I0dce63ab9fa470247c4bbd4aae58dc97cdf8a517
diff --git a/doc/source/developer/triggers.rst b/doc/source/developer/triggers.rst
new file mode 100644
index 0000000..56f4a03
--- /dev/null
+++ b/doc/source/developer/triggers.rst
@@ -0,0 +1,19 @@
+Triggers
+========
+
+Triggers must inherit from :py:class:`~zuul.trigger.BaseTrigger` and, at a minimum,
+implement the :py:meth:`~zuul.trigger.BaseTrigger.getEventFilters` method.
+
+.. autoclass:: zuul.trigger.BaseTrigger
+ :members:
+
+Current list of triggers are:
+
+.. autoclass:: zuul.driver.gerrit.gerrittrigger.GerritTrigger
+ :members:
+
+.. autoclass:: zuul.driver.timer.timertrigger.TimerTrigger
+ :members:
+
+.. autoclass:: zuul.driver.zuul.zuultrigger.ZuulTrigger
+ :members: