[server.py] rename initialisation steps for better clarity

initialisation occurs in this order:
 - object creeation (via __init__ which should consume the cfg values it knows about)
 - registering each object with the dispatcher
 - calling init_module() on each module (for connecting to other modules, checking hw, creating threads....)
 - calling start_module(cb) on each module. after the module finished startup it should call cb(self) once.
   This is the right place to do initialisation of hw which is not needed to read from the hw.
   (uploading curves, polling/re-setting all parameters, etc.)

Change-Id: Ieaf9df5876e764634836861241f58ab986027f44
Reviewed-on: https://forge.frm2.tum.de/review/18566
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>

secop/modules.py

@@ -189,21 +189,21 @@ class Module(object):
                 v.unit = v.unit.replace('$', self.accessibles['value'].unit)
 
 
-    def init(self):
+    def early_init(self):
         # may be overriden in derived classes to init stuff
-        self.log.debug('empty init()')
+        self.log.debug('empty early_init()')
 
-    def postinit(self):
-        self.log.debug('empty postinit()')
+    def init_module(self):
+        self.log.debug('empty init_module()')
 
-    def late_init(self, started_callback):
-        '''runs after postinit of all modules
+    def start_module(self, started_callback):
+        '''runs after init of all modules
 
         started_callback to be called when thread spawned by late_init
         or, if not implmemented, immediately
         '''
 
-        self.log.debug('empty late init()')
+        self.log.debug('empty start_module()')
         started_callback(self)
 
 
@@ -238,10 +238,7 @@ class Readable(Module):
                                  ),
     }
 
-    def init(self):
-        Module.init(self)
-
-    def late_init(self, started_callback):
+    def start_module(self, started_callback):
         '''start polling thread'''
         mkthread(self.__pollThread, started_callback)