feat: add CoffeeLint as dev dependencies

[ldez]

• useful for Travis CI

Related to #32

Build script (https://raw.githubusercontent.com/atom/ci/master/build-package.sh) have a special section for run automatically CoffeeLint if is present.

if [ -f ./node_modules/.bin/coffeelint ]; then
  if [ -d ./lib ]; then
    echo "Linting package..."
    ./node_modules/.bin/coffeelint lib
    rc=$?; if [ $rc -ne 0 ]; then exit $rc; fi
  fi
  if [ -d ./spec ]; then
    echo "Linting package specs..."
    ./node_modules/.bin/coffeelint spec
    rc=$?; if [ $rc -ne 0 ]; then exit $rc; fi
  fi
fi

[ldez]

I also add a better Travis CI build configuration.

For more details see: https://github.com/atom/ci

[mojavelinux]

Super! Thanks for making this improvement, @ldez!

[nicorikken]

@ldez You are so quick, it's hard to keep up :wink: :+1:

Considering the discussion on trailing whitespace in issue #47, the current version seems to make most sense. The \n would still be a good back-up solution. I have no previous experience with Travis configuration, but the definitions make sense. Also I've found a similar setup in the markdown-writer package.

I'm ready to merge this. @mojavelinux what do you think?

[mojavelinux]

:+1: (which means I vote for it)

[nicorikken]

Done so. Thanks @ldez :+1: Getting Travis test using CoffeeLint will help ensure code neatness.

[mojavelinux]

I :heart: code neatness. Nice job!