Add extra warnings in docs, and improve Makefile.

Have the shortcuts actually depends on what generate them.

docs/Makefile

@@ -87,7 +87,7 b' source/api/generated/gen.txt:'
 	$(PYTHON) autogen_api.py
 	@echo "Build API docs finished."
 
-autogen_shortcuts:
+autogen_shortcuts: autogen_shortcuts.py ../IPython/terminal/interactiveshell.py
 	$(PYTHON) autogen_shortcuts.py
 	@echo "Created docs for shortcuts"
 

docs/source/config/shortcuts/index.rst

@@ -4,6 +4,12 b' IPython shortcuts'
 
 Available shortcut in IPython terminal.
 
+.. warnings::
+
+  This list is automatically generated, and may not hold all the available
+  shortcut. In particular, it may depends on the version of ``prompt_toolkit``
+  installed during the generation of this page.
+
 
 Single Filtered shortcuts
 =========================