Speaker "play on start" property

Fixes issue: http://forums.armory3d.org/t/sound-playing-when-program-launches/621

blender/arm/exporter.py

@@ -1687,6 +1687,7 @@ class ArmoryExporter:
         o['volume'] = objref.volume
         o['pitch'] = objref.pitch
         o['attenuation'] = objref.attenuation
+        o['play_on_start'] = objref.arm_play_on_start
         self.output['speaker_datas'].append(o)
 
     def make_default_mat(self, mat_name, mat_objs):

blender/arm/props.py

@@ -186,6 +186,7 @@ def init_properties():
     bpy.types.Object.arm_proxy_sync_traits = bpy.props.BoolProperty(name="Traits", description="Keep traits synchronized with proxy object", default=True, update=proxy_sync_traits)
     bpy.types.Object.arm_cached = bpy.props.BoolProperty(name="Object Cached", description="No need to reexport object data", default=True)
     # For speakers
+    bpy.types.Speaker.arm_play_on_start = bpy.props.BoolProperty(name="Play on start", description="Play this sound automatically", default=False)
     bpy.types.Speaker.arm_loop = bpy.props.BoolProperty(name="Loop", description="Loop this sound", default=False)
     bpy.types.Speaker.arm_stream = bpy.props.BoolProperty(name="Stream", description="Stream this sound", default=False)
     # For mesh

blender/arm/props_ui.py

@@ -177,6 +177,7 @@ class DataPropsPanel(bpy.types.Panel):
             layout.prop(wrd, 'arm_lamp_ies_texture')
             layout.prop(wrd, 'arm_lamp_clouds_texture')
         elif obj.type == 'SPEAKER':
+            layout.prop(obj.data, 'arm_play_on_start')
             layout.prop(obj.data, 'arm_loop')
             layout.prop(obj.data, 'arm_stream')
         elif obj.type == 'ARMATURE':