test case for getComputedTextLength() and getBBox.width

Hello SVG WG,

I've created a test case to demonstrate the various behaviors of
getComputedTextLength() and getBBox().width on a text element across
browsers. I hope that it may serve a purpose for you, or anybody on the
mailing list. Keep up the good work!

source of the attached file: http://paste.lisp.org/display/85296#2

Best Regards,
Eric