change general/welcome.rst
change installation/index.srt
update installation/download.rst
update installation/upgrading.rst
update installation/troubleshooting.rst
update general/urls.rst
update general/controllers.rst
update general/reserved.rst
update general/views.rst
update general/models.rst
update general/helpers.rst
update general/libraries.rst
update some bug
fix some translation bug
change Codeigniter OverView
update overview
update overview
update general/requirement.rst
add .gitigore