Try to detect when people are using one version of libguile and a

Try to detect when people are using one version of libguile and a
different version of ice-9.  People have been skewing things and
sending in bug reports.
* Makefile.am (versiondat.h): New file to generate.
* version.c: #include "versiondat.h", to get version info.
(scm_libguile_config_stamp): New function.
* script.c: #include "version.h".
(scm_compile_switches): Call scm_version to get version number.
* scmconfig.h.in, Makefile.in: Regenerated.
* Makefile.in: Regenerated.

* Makefile.am (ETAGS_ARGS): Catch SCM_PROC, etc. so we can find
primitive definitions under their Scheme names.

* Makefile.am (libguile_la_LDFLAGS): Update library version to
1:2.  Helps avoid confusion between installed and uninstalled libs.