Merge branch 'master' into WIP_improve_initialization

Conflicts:
	cura/AutoSave.py
	cura/BuildVolume.py
	cura/CuraApplication.py

Contributes to CURA-5164

cura/AutoSave.py

@@ -0,0 +1,52 @@
+# Copyright (c) 2016 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
+from PyQt5.QtCore import QTimer
+
+from UM.Logger import Logger
+
+
+class AutoSave:
+    def __init__(self, application):
+        self._application = application
+        self._application.getPreferences().preferenceChanged.connect(self._triggerTimer)
+
+        self._global_stack = None
+
+        self._application.getPreferences().addPreference("cura/autosave_delay", 1000 * 10)
+
+        self._change_timer = QTimer()
+        self._change_timer.setInterval(self._application.getPreferences().getValue("cura/autosave_delay"))
+        self._change_timer.setSingleShot(True)
+
+        self._saving = False
+
+    def initialize(self):
+        # only initialise if the application is created and has started
+        self._change_timer.timeout.connect(self._onTimeout)
+        self._application.globalContainerStackChanged.connect(self._onGlobalStackChanged)
+        self._onGlobalStackChanged()
+        self._triggerTimer()
+
+    def _triggerTimer(self, *args):
+        if not self._saving:
+            self._change_timer.start()
+
+    def _onGlobalStackChanged(self):
+        if self._global_stack:
+            self._global_stack.propertyChanged.disconnect(self._triggerTimer)
+            self._global_stack.containersChanged.disconnect(self._triggerTimer)
+
+        self._global_stack = self._application.getGlobalContainerStack()
+
+        if self._global_stack:
+            self._global_stack.propertyChanged.connect(self._triggerTimer)
+            self._global_stack.containersChanged.connect(self._triggerTimer)
+
+    def _onTimeout(self):
+        self._saving = True # To prevent the save process from triggering another autosave.
+        Logger.log("d", "Autosaving preferences, instances and profiles")
+
+        self._application.saveSettings()
+
+        self._saving = False