Server type database

These patches provide an alternative way to make a dialog for editing monitoring servers.
In this way, kinds of monitoring servers and the input fields are given by Hatohol server as a JSON string. This way makes it easy to support a new monitoring server and extend parameters.

We still have the following work, but I once send the pull request to avoid divergence between this branch and the master.
- Support update of monitoring server.
- Save the extra (non-standard) parameters to the DB and pass them to Arm Plugins.

I'll do the above task within a few days and replace the current add dialog with this version by 14.09.
(Now there're two ADD buttons in server page. One is the current one, the another is this)