SVGHMI: add support for multiline widget declaration using svg:desc.

Declaration started in inkscape:label and interupted by a '\' can be continued in the description field.
After an empty line, the rest of the description field is left for description text.

from __future__ import absolute_import

from etherlab.etherlab import *
from util.BitmapLibrary import AddBitmapFolder
import util.paths as paths

AddBitmapFolder(os.path.join(paths.AbsDir(__file__), "images"))