enhance code browser(fix #235), nohead page(#161).

- fix #263. max-width of .filename was ineffective.
- fix #235. hljs replaced to aceEditor for this fix.
- make code.Browser.js less complicated
- auto-refresh for nohead page (#161)
Merge pull request #287 from laziel/codebrowser-130626

코드브라우저 관련 개선작업