[ gpsdrive ] mapnik checks in configure

[Joerg Ostertag (gpsdrive Munich/Germany)]

Hi,

i just modified the mapnik check a little bit. It now should really try to 
compile and link against the mapnik library while doing configure. If this 
fails it switches off mapnik support.
Can someone with and with out mapnik please test this too and give me feedback 
if I broke it now, or if it works.
--enable-mapnik and d--disable-mapnik should overwrite the check.

-- 

Jörg (Germany, Munich)

http://www.ostertag.name/
Tel.: +49 89 420950304
Skype: JoergOstertag