Log Message:
Import firelib from pkgsrc-wip.  Packaged by David Price and modified
by me.

C language function library for predicting the spread rate, intensity,
flame length, and scorch height of free-burning surface fires.  It is
derived directly from the BEHAVE fire behavior algorithms for
predicting fire spread in two dimensions, but is optimized for highly
iterative applications such as cell- or wave- based fire growth
simulation.