Move to es6-shim. Replace WeakMap with Map

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Accelerometer refactor

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Continued refactoring of Accelerometer class

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Adding existing example docs

- added/updated docs
Add Ray Pierce to contributors

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
es7-shim

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Track value via state side table for pin.write(val) in Pin class

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Removed dupe contributor entry
Merge pull request #337 from pierceray/dupecontrib

Removed dupe contributor entry
Support for Digital sensors

- Sensor constructor accepts type property of "digital" or "analog", defaults to "analog"
- Sensor constructor aliases:
  - Analog (pass-through)
  - Digital  (wraps implicit type="digital" setup)

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Updated grunt-contrib npm modules

- Updated grunt-contrib-jshint to 0.10.0
- Added esnext: true to allow for ES6 features
- Updated grunt-contrib-watch to 0.6.1
- Updated grunt-contrib-nodeunit to 0.3.3