Quoted font-family-names get destroyed

Created by: jazzynico

(Original report in https://bugs.launchpad.net/scour/+bug/1514073)

Font-family-names like "'MyriadPro-Regular'" get converted to "'MyriadPro-Regular'" with HTML-Entitys (primary fonts with whitespaces, because single quotation marks are recommended for this by the W3C) if you save as Optimzed SVG. Tested on Windows 7 x64 and Ubuntu latest version.

Inkscape 0.91 r13725 includes Scour 0.26+r220

Also reproduced on Xubuntu 15.10 with Scour 0.31 (as a standalone script). Test file available in the original report (unfortunately GH doesn't support SVG attachments...).