This patch updates the hsm subcommand in barbican-manage to read
any required values from barbican.conf. Users may continue to
specify those values as parameters in the command line, and those
values will take precedence over values in barbican.conf.
Existing scripts that call barbican-manage should continue to work
as expected as the values passed will be used instead of looking
into barbican.conf.
Change-Id: I4e86e73bbdef0e16d3699cec1cc8f7e17dfb643b
666034475a