Update API to 0.5

Add initiator_set_auth method.

Signed-off-by: Andy Grover <agrover@redhat.com>
Add support for initiator_set_auth

Added in API 0.5. This allows iscsi exports to optionally require login
credentials via CHAP. It also enables mutual authentication. The
target's credentials are set globally in the config file.

Signed-off-by: Andy Grover <agrover@redhat.com>
Edit README.md for current config file format

Untested, but hopefully correct.

Signed-off-by: Andy Grover <agrover@redhat.com>