Re #4311. Return the docstring of the proxied object.

This helps the correct documentation string show up in the IPython console.
I've also turned on automatic docstring generation in our sip call.

Code/Mantid/MantidPlot/CMakeLists.txt

@@ -518,7 +518,7 @@ set( SRC_UNITY_IGNORE_FILES )
 add_custom_command ( OUTPUT ${SIP_SRC_AUTO}
                      COMMAND ${SIP_EXECUTABLE}
                           -I ${PYQT4_SIP_DIR} -I ${CMAKE_CURRENT_SOURCE_DIR}/../MantidQt/Python ${PYQT4_SIP_FLAGS}
-                          -c ${CMAKE_CURRENT_BINARY_DIR} -j1 -w 
+                          -c ${CMAKE_CURRENT_BINARY_DIR} -j1 -w -o
                           ${SIP_SPEC}
                      DEPENDS src/qti.sip ${SIP_HDRS}
                      COMMENT "Generating python bindings using sip"

Code/Mantid/MantidPlot/mantidplotpy/proxies.py

@@ -29,6 +29,7 @@ class CrossThreadCall(QtCore.QObject):
         QtCore.QObject.__init__(self)
         self.moveToThread(QtGui.qApp.thread())
         self.__callable = callable
+        self.__call__.__func__.__doc__ = callable.__doc__
         
     def dispatch(self, *args, **kwargs):
         """Dispatches a call to callable with