usability: display all supported parameters for fleetd

[kayrus]

Current behavior:

fleetd --help
Usage of fleet:
  -config="": Path to config file. Fleet will look for a config at /etc/fleet/fleet.conf by default.
  -version=false: Print the version and exit

Expected behavior:

fleetd --help
Usage of fleet:
  --config="": Path to config file. Fleet will look for a config at /etc/fleet/fleet.conf by default.
  --version=false: Print the version and exit
  --verbosity
  --etcd-servers
  --etcd-request-timeout
  --etcd-cafile
  --etcd-keyfile
  --etcd-certfile
  --etcd-key-prefix
  --public-ip
  --metadata
  --agent-ttl
  --engine-reconcile-interval
  --disable-watches
... ... ...

Also relates to this issue: coreos/docs#650

[reneengelhard]

are you sure this is correct? the code only honours them if it's from the config

[jonboulle]

Right, as we just discussed OOB, this is actually working as expected - fleetd doesn't take options, and we'll need to revert part of aae37e1