Added additional functions

toPitch: takes a sound file, creates a pitch object from it and saves it to file. Very, very slow. 
pitchAtMaxIntensity: takes a pitch object and time and extracts the pitch at that time. CURRENTLY BROKEN, returns only --undefined-- 
toPitchTier: takes a pitch object, creates a pitch tier object and saves it to file.
pitchFromPitchTier: takes a pitch tier object and time point and returns the pitch at that time. 

In order to extract pitch from a given point, you need to follow this progression: .wav -> .pitch -> .pitchTier -> extract pitch from .pitchTier
I'd like to be able to take pitch directly from the pitch object but I can't get it to work.