[Tilesathome] less inkscape calls in _unstable

[Sebastian Spaeth]

Matthias Julius wrote:

> This seams sensible.  That's what I'll do if nobody objects.

I object, see my previous mail. I don't think that our default 
configuration should prohibit the rendering of a share of our tiles. 
Most people are going to run the default values and I don't want to lose 
out on any renderer that can potentially handle a complex tile because 
the owner didn't bother to change the defaults (can't blame them for it)

If everyone else thinks differently, override me, but i am against it.
spaetz