Add skipping mechanism autodoc

It currently just skips __init__ like the old one did
Refs #9624

Code/Mantid/docs/source/conf.py

@@ -23,7 +23,8 @@
     'sphinx.ext.autodoc',
     'sphinx.ext.intersphinx',
     'sphinx.ext.doctest',
-    'mantiddoc.directives'
+    'mantiddoc.directives',
+    'mantiddoc.autodoc'
 ]
 
 #try: # bonus for doxygen links - TODO off for now

Code/Mantid/docs/sphinxext/mantiddoc/autodoc.py

@@ -0,0 +1,24 @@
+"""
+Mantid customizations for the behaviour of the Sphinx autodoc
+extension
+"""
+
+def skip(app, what, name, obj, skip, options):
+    """
+    Arguments:
+      app: Sphinx application object
+      what: the type of the object which the docstring belongs to (one of "module", "class", "exception", "function", "method", "attribute")
+      name: the fully qualified name of the object
+      obj: the object itself
+      skip: a boolean indicating if autodoc will skip this member if the user handler does not override the decision
+      options: the options given to the directive: an object with attributes inherited_members, undoc_members, 
+               show_inheritance and noindex that are true if the flag option of same name was given to the auto directive
+    """
+    if name == "__init__":
+        return False
+    return skip
+
+def setup(app):
+    # Define which methods are skipped when running autodoc
+    # on a member
+    app.connect("autodoc-skip-member", skip)