Merge pull request matplotlib#4418 from RealGeeks/master

FIX: font weight handling in svg

Merged by hand to drop two merges from master into this branch

Author: tacaswell

lib/matplotlib/backends/backend_svg.py

@@ -1030,7 +1030,7 @@ def _draw_text_as_text(self, gc, x, y, s, prop, angle, ismath, mtext=None):
             style['font-size'] = six.text_type(fontsize) + 'px'
             style['font-family'] = six.text_type(fontfamily)
             style['font-style'] = prop.get_style().lower()
-            style['font-weight'] = prop.get_weight().lower()
+            style['font-weight'] = six.text_type(prop.get_weight()).lower()
             attrib['style'] = generate_css(style)
 
             if mtext and (angle == 0 or mtext.get_rotation_mode() == "anchor"):