Fix typo
Introduce configuration file
Remove a needless assignment
Add a missing space before "="
Name floating NodeStatus instance
Use "status" instead of "node_status"

Because other codes in the same file use "status".
Use instanciated @serf instead of class methods of Serf
Remove "send_query" class method
Return nil expressly for the failure case
Output more logs for debugging
Use "host" as the host name of the node itself, instead of "joining_node", because "host" is detected based on Serf's name
Fix missing "Droonga::" prefix
Fix missing variable error for catalog
Give nodes as arguments, not an array argument
Don't parse non-JSON output as a JSON
Merge pull request #17 from long-long-float/introduction-of-configuration-file

Introduce configuration file