Cannot find BlenderVR root

gistfile1.txt

$ ./blendervr --BlenderVR-root=. start -configuration ../samples/basic.xml -screen 'Fullscreen' -processor "../samples/basic/head-navigation/roomVR.processor.py" -blend "../samples/basic/head-navigation/roomVR.blend"
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        BlenderVR Copyright (C) LIMSI-CNRS (2014)
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Traceback (most recent call last):
  File "./modules/blendervr/console/logic/console.py", line 231, in update_user_files
    self._processor = processor(self)
  File "/home/haliyo/Development/Blender-VR/samples/basic/head-navigation/roomVR.processor.py", line 111, in __init__
    from blendervr.interactor.head_controlled_navigation import HCNav
  File "./modules/blendervr/interactor/head_controlled_navigation.py", line 278, in <module>
    from ..tools.gui.qt import QtGui
  File "./modules/blendervr/tools/gui/qt.py", line 42, in <module>
    from PySide import QtGui, QtCore
ImportError: No module named 'PySide'

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Traceback (most recent call last):
  File "./modules/blendervr/console/logic/console.py", line 231, in update_user_files
    self._processor = processor(self)
  File "/home/haliyo/Development/Blender-VR/samples/basic/head-navigation/roomVR.processor.py", line 111, in __init__
    from blendervr.interactor.head_controlled_navigation import HCNav
  File "./modules/blendervr/interactor/head_controlled_navigation.py", line 278, in <module>
    from ..tools.gui.qt import QtGui
  File "./modules/blendervr/tools/gui/qt.py", line 42, in <module>
    from PySide import QtGui, QtCore
ImportError: No module named 'PySide'

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Traceback (most recent call last):
  File "./modules/blendervr/console/logic/console.py", line 231, in update_user_files
    self._processor = processor(self)
  File "/home/haliyo/Development/Blender-VR/samples/basic/head-navigation/roomVR.processor.py", line 111, in __init__
    from blendervr.interactor.head_controlled_navigation import HCNav
  File "./modules/blendervr/interactor/head_controlled_navigation.py", line 278, in <module>
    from ..tools.gui.qt import QtGui
  File "./modules/blendervr/tools/gui/qt.py", line 42, in <module>
    from PySide import QtGui, QtCore
ImportError: No module named 'PySide'

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Traceback (most recent call last):
  File "./modules/blendervr/console/logic/console.py", line 231, in update_user_files
    self._processor = processor(self)
  File "/home/haliyo/Development/Blender-VR/samples/basic/head-navigation/roomVR.processor.py", line 111, in __init__
    from blendervr.interactor.head_controlled_navigation import HCNav
  File "./modules/blendervr/interactor/head_controlled_navigation.py", line 278, in <module>
    from ..tools.gui.qt import QtGui
  File "./modules/blendervr/tools/gui/qt.py", line 42, in <module>
    from PySide import QtGui, QtCore
ImportError: No module named 'PySide'

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Waiting for daemons to start...
Daemon Started!!!
Starting Simulation...
Traceback (most recent call last):
  File "./blendervr", line 177, in <module>
    module.main()
  File "./utils/console.py", line 100, in main
    console.main()
  File "./modules/blendervr/terminal/terminal.py", line 127, in main
    ui.UI.main(self)
  File "./modules/blendervr/terminal/ui/ui.py", line 59, in main
    self._start_mode()
  File "./modules/blendervr/terminal/ui/ui.py", line 118, in _start_mode
    self.start_simulation()
  File "./modules/blendervr/console/logic/console.py", line 287, in start_simulation
    if self._processor.useLoader():
AttributeError: 'NoneType' object has no attribute 'useLoader'
Cannot find BlenderVR root !
Try adding --BlenderVR-root option to BlenderVR (./blendervr --BlenderVR-root="path") !