BBBikeXS.xs
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Some time-critical functions for bbbike coded in C/XS.

strecke() in BBBikeXS.xs now uses an integer variant of sqrt()
(implementation is in sqrt.c). The times for making the net dropped on
the iPAQ from 8.32s to 7.12s.

Send comments to Slaven Rezic <slaven@rezic.de>.
