Bug fix Util::highlithg_keywords

Change algorithm
Refactoring
Ignore case in Util#highlight_keywords
Highlight keywords
Modify highlight color
Bug fix
Add TestCdwebApp#t_view_with_query

f.g. http://url/home/a_project/cdstk.rb?query=def
Add TestCdwebApp#t_view_simple, t_view_gotoline
Add TestCdwebApp#t_search_contents, t_search_gotolne, t_search_fuzzy_gotoline
Comment out
Add feature to delete HTML tag in Util#highlight_keywords
Undo mistake
Adjust color
Adjust color .select-line
Touch update time if exist update file
Add github button if exist yaml_pacakge.options[:github]
GitHub repository check in 'milk update'

Util::githu_repo is still mock
Implement Util::github_repo
Have forgotten Dir#chdir
Merge branch 'feature/github-button' into develop