Formatted READ.ME

Added more informative README

Added doorbell alert + file

using full path on environment variables

Updated to use folder paths

Promisified code and added module exports

Updated filename generation step to create unique file handles for S3

Added tmp folder + placeholder and updated S3 to use timestamped images (in order to retain images and prevent overwriting previous images)

Modified package.json to include aws-sdk

Merge branch 'master' of https://github.com/garbit/dash-doorbell

Adding project files

Initial commit