Change sync fs calls to use assert style return values and errors
Style fix
Merge pull request #55 from luvit/error-of-good-report

Change sync fs calls to use assert style return values and errors
Strictly check type on booleans
Fix for windows
fix bug https://github.com/luvit/luv/issues/59
Merge branch 'master' of https://github.com/zhaozg/luv