Adding Sathya's changes to MS to offlineProcessing

Also adding switch case to main.m file - you can simply run this main.m
file

Problem:
When the gain function’s output is connected to the IFFT, the error
received is:
Error in 'offlineProcessing/Inverse
Transform & Overlap-Add/Inverse
Short-Time FFT/Buffer': All sample
times must be discrete. No continuous
or constant sample times are allowed.