Reduce size of data sent to server

1. Reduce ecgDerivedRate, impedanceRate, impedanceQuality attributes in
Chest Data
2. Disabled phone accelerometer/light data transmission to server
Survey UI Modified Merge

Survey UI Modified
Add new Accelerometer Interface

Need to override the unimplemented methods later
Merge pull request #1 from MUSensingLab/master

Interface added
Merge pull request #4 from RickyShi/master

Merge Test