Build bin/{barnowl,tester} instead of {barnowl,tester}.bin

This lets us get rid of some silly install and uninstall hooks.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
barnowl --help: Write to stdout and exit successfully

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
zcrypt: Use getopt_long

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
zcrypt: Accept --version

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
zcrypt: Accept --help

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Check that programs support --help and --version in ‘make installcheck’

Also, put ‘foreign’ before ‘-Wall’ because automake ≥ 1.10, < 1.12 may
interpret the other order differently:
  http://debbugs.gnu.org/cgi-bin/bugreport.cgi?bug=7669

Signed-off-by: Anders Kaseorg <andersk@mit.edu>