strokeadjust:ing by default

[Alexander Malmberg]

Recently, I reworked back-art's handling of strokeadjust. In postscript. 
strokeadjusting will move points of paths around a bit to try to line 
things up with device pixels and make line widths seem more uniform. In 
back-art, I do things that are similar in spirit: adjust points on 
paths, line widths, and dash offsets to make the results sharper and 
clearer. The drawback of this is that by moving things around, you 
distort the paths a bit.

As an example, here a are a bunch of lines without strokeadjusting:

http://web.telia.com/~u42308495/alex/backart/lines_strokeadjust_off.png

and with:

http://web.telia.com/~u42308495/alex/backart/lines_strokeadjust_on.png

Note that with strokeadjusting, the results are much sharper. However, 
the results without strokeadjusting are more accurate: the lines really 
are placed "between" pixels.

back-art used to apply some simple adjusting always, but I've now 
changed it so that it's only applied when strokeadjusting is on, and, 
after thinking about it a bit, it seems best to me to enable it by 
default. All of the normal views benefit from clear rendering on screen, 
so it seems better to have the exceptions turn strokeadjusting off than 
to make everyone else have to turn it on all the time.

Thus, unless there are any serious objections, I'll commit that shortly. 
In cases where you really need accurate rendering, remember to call 
PSsetstrokeadjust(0) before drawing (e.g. in -setUpGState).

- Alexander Malmberg