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

- add fillstitch to loadFromFile method

- display the bounding box of the selection

- add an initNewDocument method in OE_controller
- if OE_document::getBound is called in an empty document it return the hoop bound
- change the keyboard shortcut S key to L for creating linestitch to avoid problem with CTRL+S

-use /dev/rfcomm1 for controler creation

- 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

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

second move to a MVC design

add a OE_svgParser class to fill the document
first move to a MVC design

subcurve only work if start<end for now