Fixes and additions to strategies

src/main/java/com/example/stimulus/SedentaryStimulus.java

...main/java/com/example/stimulusStrategy/Accelerometer.java

...in/java/com/example/stimulusStrategy/SigMotionDetect.java

src/main/java/com/example/stimulusStrategy/StepCounter.java

src/main/res/values/integers.xml