fix some signal-slot issues

Qt port: fix controller document, fix keyboard modState, fix key event redirection, fix last tab close bug, fix menu emulated shortcuts, add pakal to build

- cleanup unused code in OE_interfaceDisplay::mouse_Pos method

- change the way to make linestitch and birailstitch (trace only one segment by default, remove validation with "return" key)

  OE_actionScaleSelectedStitchLen
  OE_actionScaleSelectedStitchWidth
  OE_actionSetSelectedStitchPattern
- fix memory leaks when deleting meta actions:
  OE_actionScaleSelectedBirailStitchLen
  OE_actionScaleSelectedLineStitchWidth
  OE_actionScaleSelectedLineStitchLen
  OE_actionSetSelectedLineStitchPattern
  OE_actionSelectionClear

- add an option to warpStitch method to use 2 lines instead 1 line and 1 normal array

- fix a pan problem (2 time slower than the mouse move)
- add a backgroundColor in displayStyle

- fix a pan problem (2 time slower than the mouse move)
- add a backgroundColor in displayStyle

- add OE_actionDelPointLinkStitch and make it work

- make linkStitches point pickable

- remove the OE_commandDisplay class (specific functions are merged in OE_diplay)

- add a lot of displayStyle variables

- warpStitch include now x and y offset for pattern translation
- add xOffset and patternSteps attribute to linestitch and rename offset to yOffset

- set the OE_controler to use the SERIALPORT environment variable
- change the default creation values of linestitch lenth and width