Remove autogenerated files

Remove autogenerated files

The removed files are generated using bootstrap
(libtoolize, autoreconf) and they are available in release tarballs.

- Avoids outdated configure file in git
- Resolves #1163
- The following commands have been used for removal:
  git rm configure
  git rm -r conftools/
  git rm Makefile.in
  git rm *Makefile.in
  git rm src/rrd_config.h.in