* Switch to autoreconf in autogen.sh
* Rename configure.in to configure.ac
* Use modern form of AC_INIT and AM_INIT_AUTOMAKE
* Set "foreign" automake option to avoid creation of a default
  COPYING and INSTALL.
* Remove AC_PATH_PROG(RM), otherwise libtool's $RM will be overwritten
  and cause the infamous "cannot remove libtoolT" warning.
* Remove autogenerated config.h.in from version control
* Update .gitignore