Merge pull request #6 from tjmahr/master

Major revision to NWR transcription
Merge pull request #10 from tjmahr/master

transition to next type of trial when finished with CV trials
remove non-English phonemes from menus
Update segment_features.praat
support for voiced and unvoiced lateralized fricatives
stub/placeholder for notes prompt
add third point (syllable number) for prosody scoring
make vowel transcription more user-friendly by defaulting to the correct feature values in the drop-down menus