Implemented Configuration Parser
Refactor packages
Port, Cache Directory, Repository can be configured in config file

	deleted:    Config.hs
	modified:   Main.hs
	modified:   XTag/Config.hs
	renamed:    Model/Book.hs -> XTag/Model/Book.hs
	renamed:    Model/Type.hs -> XTag/Model/Type.hs
	renamed:    Model/Util.hs -> XTag/Model/Util.hs
	deleted:    test.config
Merge branch 'master' of github.com:yeyan/xtag