Merging upstream version 2.3.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

.gitignore

@@ -0,0 +1,37 @@
+*.o
+*.lo
+*.la
+config.log
+config.status
+stamp-h1
+ar-lib
+config.guess
+config.sub
+libtool
+ltmain.sh
+.deps
+.libs
+Makefile
+Makefile.in
+src/dnscap
+src/dnscap.1
+autom4te.cache
+Makefile.old
+aclocal.m4
+compile
+configure
+configure~
+depcomp
+install-sh
+missing
+test-driver
+config.h
+config.h.in~
+m4/libtool.m4
+m4/ltoptions.m4
+m4/ltsugar.m4
+m4/ltversion.m4
+m4/lt~obsolete.m4
+build/
+config.h.in
+dnscap-[0-9]*tar*