Add "hook" and "module" to glossary

Author: tilgovi

doc/glossary.rst

@@ -6,6 +6,18 @@ Glossary
 .. glossary::
    :sorted:
 
+   hook
+      A function that handles work delegated to a :term:`module` by the
+      :term:`application`. A hook function can return a value or a
+      :term:`Promise`. The arguments to hook functions can vary. See
+      :ref:`module-hooks` for a description of the core hooks provided by
+      Annotator.
+
+   module
+      A module extends the functionality of an :term:`application`, primarily
+      through :term:`hook` functions. See the section :doc:`module-development`
+      for details about writing modules.
+
    Promise
       An object used for deferred and asynchronous computations.
       See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise

doc/module-development.rst

@@ -4,7 +4,7 @@ Module development
 The basics
 ----------
 
-An Annotator module is a function that can be passed to
+An Annotator :term:`module` is a function that can be passed to
 :func:`~annotator.App.prototype.include` in order to extend the functionality of
 an Annotator application.