Fixed many bugs in gpg-opts.sh
Fixed many bugs in gpg-opts.sh

Show usage info if no arg is provided to the script.

Fixed the logic testing AG_GPG_PASSPHRASE and AG_GPG_PASSPHRASE_FILE

Fixed the test for passphraseless keys.  Prior to this it would just
block, waiting for input on stdin.

Fixed the call to 'read' which used single quotes around the
${GPG_PROMPT}, preventing it form being expanded.

Change-Id: Idb321d055f8e6fb01370f4d24e6b4a414c457844
Reviewed-on: https://gerrit.franz.com:9080/12286
Tested-by: Hudson <dfb64870173313a9a7b56f814c8e3b33e268497a@franz.com>
PTEST: Hudson <dfb64870173313a9a7b56f814c8e3b33e268497a@franz.com>
Reviewed-by: Tadeusz Sznuk <4402abb98f9559cbfb6d73029f928227b498069b@franz.com>
Reviewed-by: Ahmon Dancy <8f7d8ce2c6797410ae95fecd4c30801ee9f760ac@franz.com>

franzinc/agraph-python,franzinc/agraph-python,franzinc/agraph-python,franzinc/agraph-python