Make stick_client raw_device() return the socket
Add option to run yhsm-daemon as a proper daemon
Add option to run yhsm-yubikey-ksm as a proper daemon

Uses https://pypi.python.org/pypi/python-daemon/ library.
Add option to write pid file

This option is similar to the one that already exists for yhsm-yubikey-ksm
Add python-daemon dependency
Merge pull request #9 from alexjfisher/daemonise

Use python-daemon to properly daemonize yhsm-daemon and yhsm-yubikey-ksm