On non-Windows systems, try /dev/random and, if it exists, use it,

On non-Windows systems, try /dev/random and, if it exists, use it,
otherwise fall back on time().

Print error messages to stderr, and put the name of the program in them.
Exit with 1 on command-line syntax errors, 2 on other errors.

Fix indentation.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@26661 f5534014-38df-0310-8fa8-9805f1628bb7