Update README.md, add .sass-cache to .gitignore
Server port defined in a config
Use original server port as default
Merge pull request #4 from aobyrne/master

Allow server port to be easily changed via a config
Fix error handling

Compile errors would properly report, but cause the gulp task to
hang. This commit abstracts out a resusable error handler that sends
errors to notification center, AND emits an 'end' event, so that gulp
moves on from the task.