Two helper scripts for porting Unbound:

 - freebsd-configure.sh runs ./configure with the correct parameters
   and regenerates the lex and yacc code.

 - freebsd-sources.pl untangles the upstream Makefile and generates
   source lists for our Makefiles.

Approved by:	re (blanket)
Move prototypes into header.

Approved by:	re (blanket)