add a dependent package for `grunt typo`

  - estraverse 1.5.0
:muscle: improve `grunt typo` to detect more typo
:boom: fix typo
update dependent packages

  - coveralls 2.10.1
  - grunt-jscs-checker 0.5.1
update jscs configuration

  - requireSpaceAfterLineComment: true
Merge pull request #90 from mohayonao/dev-tools

update development tools