updates to FM and AM patches
Merge branch 'master' of https://github.com/cmuphyscomp/physcomp-examples

Conflicts:

1_energy-information-transduction/c_pd-starter/iii_advanced-pd-music/1.c
.iii.6_music-synth-am-fm/1.c.iii.6_music-synth-am-fm.html