Merge pull request #12 from boredivan/gh-pages

2 translated articles
merge two book-intro
Merge pull request #14 from boredivan/gh-pages

continuing on translation
Merge pull request #15 from boredivan/gh-pages

1 translated article
Merge pull request #16 from boredivan/gh-pages

1 translated article: vim_command_rule.md
1 translated article: vim_help.md