added script to determine current version

if exactly on tag, it returns the tag itself, ex.: 4.0.2
otherwise it returns the incremented last tag plus the
current date, ex.: 4.0.3_20131112

It works great with the update version script
ex.: ./update-version $(./get_version)
which is used for automatic builds.
removed some autogenerated files

these files are autogenerated and should therefor not be included in the repository.