add svg loading code from stackoverflow.

Starting work on https://github.com/shlomif/PySolFC/issues/3 .

pysollib/ui/tktile/svg.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+# vim:fenc=utf-8
+#
+# Distributed under terms of the CC-BY-SA licence, see:
+# https://stackoverflow.com/questions/22583035
+# Thanks!
+
+
+def svgPhotoImage(file_path_name):
+    import Image
+    import ImageTk
+    import rsvg
+    import cairo
+    "Returns a ImageTk.PhotoImage object represeting the svg file"
+    # Based on pygame.org/wiki/CairoPygame and http://bit.ly/1hnpYZY
+    svg = rsvg.Handle(file=file_path_name)
+    width, height = svg.get_dimension_data()[:2]
+    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, int(width), int(height))
+    context = cairo.Context(surface)
+    # context.set_antialias(cairo.ANTIALIAS_SUBPIXEL)
+    svg.render_cairo(context)
+    tk_image = ImageTk.PhotoImage('RGBA')
+    image = Image.frombuffer('RGBA', (width, height), surface.get_data(),
+                             'raw', 'BGRA', 0, 1)
+    tk_image.paste(image)
+    return tk_image