FreeBSD platform support (build and runtime)

This changes allow to properly compile and run it on FreeBSD, they included:
* autotools support to set [LDLIBS](https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html) library flags
* usage of [getprogname(3)](http://www.freebsd.org/cgi/man.cgi?query=getprogname) call instead of relying on procfs (/proc/curproc/cmdline) or linprocfs (/compat/linux/proc/self/cmdline)
* remove bash-isms in *logfaf.in* script

Also, it complete and fixes issue #5, thanks!