Added extra-hosts to wakame-init.
fix wakame-init.
Removed unnecessary space.
use Sinatra::Base#content_type to set API response format since respond_with seems to prefer this way.
refactor setup extra-hosts.
changed sed command parameter.
changed comment message.
fix egrep parameter.
changed search condition to full match.
changed so that create tmpfile of a random name.
Merge pull request #255 from axsh/fix-api-response-content-type

Enhancement for setting sinatra response type
Merge pull request #253 from axsh/feature-wakame-init-extra-hosts

Added extra-hosts to wakame-init.
Merge pull request #256 from axsh/feature-volume-localstore

fix API response error from "GET /instances/i-xxxxx/volumes".
add mussel command "instance show_volumes" & "instance backup_volume".
set default guest_device_name for linux containers when migration 0014 runs.