update the readme

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

- make first and last point move together when form is closed

- use it in OE_actionMovePointCurve
- clear OE_actionSetPointCurve (not used)

- 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

- store the len value of the birailStitch
- add the move function to staticStitch
- add getStitchStart and getStitchEnd method to OE_linkstitch
- fix a bug in OE_linkstitch::refresh method (it always put needRefresh to false)
- add double point motif to OE_linestitch
- add OE_actionDelStitch
- fix a bug in refreshDependency of most stitches and curves (does not refresh dependency of their own dependency)

- add actions for moves
- add - operator to vector_2d class

- fix a refresh bug in getBound method of curve class

- display the bounding box of the selection

- add a refreshDependency function to refresh every dependency link (execute addDependency(this) in each parent of a child)

- fix problems on linestitch interactive creation

- 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 some actions to clear selections

- now discretized points are stored in a new 2d point type "vector_2dt" witch store the t parameter too

- 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

- create an actionSelection only when there is a selection

- 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)