Fix for rename issue

Java apparently can't rename files under linux, so as a substitute an
option has been added for how to deal with renaming. The default, no
commands install file now creates a backup and then attempts to
uninstall/install BTH. This will fail if renaming is not enabled. If
this occurs a user can then restore the backup and run BTH from the
command line, which will not attempt to rename files, solving the issue.