Segment fixes

[bambooforest]

Some incorrect conventions stuff discovered in regard to #225 including:

n̥n | uz ɲ̥ɲ̥ | uz ŋ̊ŋ | uz

Fix em.

[bambooforest]

@drammock - these all come from the same description (Burmese) in which it says (x3):

"the voiceless sonorant /n̥/ is typically partly voiced [n̥n]"

Suggestions?

[drammock]

1. move all rings to be inferior
2. it looks like the second example has devoicing rings on both segments? That's probably a mistake.