Update AccelerationInitializer.java

when I use the library by your demo,I have a java.lang.IllegalArgumentException.
nextInt(int n) Returns a pseudo-random uniformly distributed int in the half-open range [0, n).
If this file change doesn't need to do.please overlook
Update AccelerationInitializer.java

1.fix (mMaxAngle - mMinAngle) can be set 0 or a negative number
Merge pull request #3 from Haoxiqiang/master

Update AccelerationInitializer.java