Bump immutable library, fix changes to updateIn API
Code review.
Prevent jshint warnings.
Bump version to 2.0.3. Require Immutable 2.0.14 or higher.
CommonJS modules, simplify build process

Adds browserify & several npm scripts in place
of most grunt tasks. Saves a few kb on minified
build (due to no longer needing almond / urequire).

Spacing is maintained for minimal diff noise in this
commit.
Whitespace cleanup & built UMD files
Export Main.js, add doc script in npm scripts, eliminate Gruntfile
Merge pull request #10 from tgriesser/cjs

CommonJS modules, simplify build process.
Update to Immutable 2.0.15.