doc: update normalize command document
doc: update normalize command document

There are many TODOs. We should add one or more examples to each
description! Because example is very helpful to understand. We should
think about users.

redfigure/groonga,cosmo0920/groonga,komainu8/groonga,kenhys/groonga,naoa/groonga,cosmo0920/groonga,komainu8/groonga,redfigure/groonga,komainu8/groonga,groonga/groonga,hiroyuki-sato/groonga,myokoym/groonga,myokoym/groonga,komainu8/groonga,redfigure/groonga,naoa/groonga,komainu8/groonga,redfigure/groonga,myokoym/groonga,myokoym/groonga,kenhys/groonga,redfigure/groonga,redfigure/groonga,komainu8/groonga,cosmo0920/groonga,myokoym/groonga,hiroyuki-sato/groonga,myokoym/groonga,groonga/groonga,naoa/groonga,naoa/groonga,kenhys/groonga,groonga/groonga,groonga/groonga,naoa/groonga,groonga/groonga,kenhys/groonga,myokoym/groonga,kenhys/groonga,groonga/groonga,kenhys/groonga,hiroyuki-sato/groonga,cosmo0920/groonga,komainu8/groonga,komainu8/groonga,groonga/groonga,naoa/groonga,hiroyuki-sato/groonga,hiroyuki-sato/groonga,cosmo0920/groonga,kenhys/groonga,hiroyuki-sato/groonga,hiroyuki-sato/groonga,cosmo0920/groonga,hiroyuki-sato/groonga,redfigure/groonga,cosmo0920/groonga,groonga/groonga,redfigure/groonga,myokoym/groonga,cosmo0920/groonga,naoa/groonga,naoa/groonga,kenhys/groonga