[Design-team] SVG rendering performance

[Charlie Brej]

If we choose to distribute SVGs as the default background files, it may be an 
idea to examine the rendering speed. On my rather old home machine, it takes 
over two minutes to draw the mosaico SVG background [1] with the CPU running 
flat out. What really increases the cpu demand is the use of blur. Removing all 
blur brings it down to 3 seconds (about the same as other PNG/JPEG backgrounds).
We should also remove all the additional XML fluff inkscape puts into the files.

[1] 
http://fedorapeople.org/groups/designteam/Resources/Fedora%20Release%20Themes/F12/Sources/Alpha%20Proposals/wallpaper-mosaico6c_mo.svg