Refactor file io system, move oe format to custom manager, dynamic dialog filters and format management

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

- uniformise color of every interactive controls of the curves and stitch

- 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

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

- add a lot of displayStyle variables

- add OE_controller::getSelectionBoundingBox function
- rename "select" function to "picking" in OE_interfaceDisplay (more clear name)
- change selection mode into an editionState in OE_interfaceDisplay
- add scale method to curves and stitchs
- add ScaleSelection state and implement the scale selection actions and UI widget
- clean and comment OE_interfaceDisplay
- add BoundingBox::getCenter method
- add OE_display::screenToDocument method

- display the bounding box of the selection

- add creations function
- change functions in joincurve class to insert new curves anywhere and remove them
- add an action to create and add a subcurve to a joincurve

- add editLastAction function to OE_controller to make possible "live modification"
- add OE_actionSetPointCurve and OE_actionMovePointCurve to OE_actionCurves
- add setPoint function to OE_pointcurve and change getPoint to use reference instead of pointer

- add instructions class
- add hoop, pulse/mm and zero point in document

- replace the array (curves, stitches, threads,...) by list to be more flexible with delete and moves of elements
- refresh curves only when needed

declare dependents objects to their reference (to be able to remove the reference without error)

- draw controls only for the selected curves and stitchs

- fix a bug in birailstitch class (initialisation of len and maxlen variable was not set)
- add the display of a point at 0,0

add thread class (stitch one, not computing) to deal with color, width and later (maybe) rendering style

- bug fix in curves (the subcurve function return bad path in case of start and end both on the same segment)