T controller tutorial and improve documentation

add tutorial for Berlin hands-on workshop

+ improve the documentation (hints for structure welcome)
+ remove 'optional' parameter property
  (is not yet used - should not appear in doc)
+ added test property in frappy_demo.cryo alters Parameter class
  ('test' property appears in Parameter doc)

Change-Id: I3ea08f955a92f72451fd23a5ff00d1185c7fb00e

doc/source/configuration.rst

@@ -0,0 +1,58 @@
+Configuration File
+..................
+
+.. _node configuration:
+
+:Node(equipment_id, description, interface, \*\*kwds):
+
+    Specify the SEC-node properties.
+
+    The arguments are SECoP node properties and additional internal node configurations
+
+    :Parameters:
+
+        - **equipment_id** - a globally unique string identifying the SEC node
+        - **description** - a human readable description of the SEC node
+        - **interface** - an uri style string indication the address for the server
+        - **kwds** - other SEC node properties
+
+.. _mod configuration:
+
+:Mod(name, cls, description, \*\*kwds):
+
+    Create a SECoP module.
+    Keyworded argument matching a parameter name are used to configure
+    the initial value of a parameter. For configuring the parameter properties
+    the value must be an instance of **Param**, using the keyworded arguments
+    for modifying the default values of the parameter properties. In this case,
+    the initial value may be given as the first positional argument.
+    In case command properties are to be modified **Command** has to be used.
+
+    :Parameters:
+
+        - **name** - the module name
+        - **cls** - a qualified class name or the python class of a module
+        - **description** - a human readable description of the module
+        - **kwds** - parameter, property or command configurations
+
+.. _param configuration:
+
+:Param(value=<undef>, \*\*kwds):
+
+    Configure a parameter
+
+    :Parameters:
+
+        - **value** - if given, the initial value of the parameter
+        - **kwds** - parameter or datatype SECoP properties (see :class:`frappy.param.Parameter`
+          and :class:`frappy.datatypes.Datatypes`)
+
+.. _command configuration:
+
+:Command(\*\*kwds):
+
+    Configure a command
+
+    :Parameters:
+
+        - **kwds** - command SECoP properties (see :class:`frappy.param.Commands`)