Reconsider reliance on 'localhost'

[mfeit-internet2]

In the library's api.py, this function could be made smarter.

def api_local_host_name():
    "Return the local system's hostname"
    return socket.gethostname()

What it returns now requires that the system's hostname be resolvable. The steps should be as follows:

• If the hostname resolves, use that.
• If not, find the IP of a loopback interface and use that.
• Otherwise, throw an exception.

[mfeit-internet2]

Relase Notes:

pScheduler no longer relies on the system's host name being resolvable to an IP address. While having a resolvable host name is still a recommended practice, it will now revert to the address of a loopback or other interface in its absence.