Move to automake

The build system is now based on automake, so all the hand crafted
code in Makefile.in is gone

What works:
- building of loaddefs, byte compiling and installation of lisp files
- building and installation of documentation
- for now tex files are simply packaged and installed in pkgdatadir, i.e. /usr/local/share/bbdb

What needs to be done:
- The conditional build with the vm-dir is there but hasn't been tested
- the loaddefs are done for vm even if it isn't installed
Ignore generated files