remove the accelerometer and rotation vector sensor

make code more efficient. Doing less file I/O
stop update values to the display, since it's useless cuz it's changing
so fast
fix bugs in timestamp
Add calibration and fix write to file bugs
add neural networks to the application
add read training data from file function for neural network
add normalization process
add async tasks to burden off the ui thread
add threshold triggered training data collection method
add method to collect linear acceleration data
fixed the bug of sensor values. Make keyStrokeSampleData in to MSensor Class
add recording 5 sample points before the sample that run over the threshold value
fixed toast update bug
use gyro to control the starting collections of linear accelerometer
Update README.md
Update README.md
Merge pull request #1 from Jamesjue/linearAcc

Merge Master to linearAcc