add sys:get-env
add setenv & unsetenv
improvements to printing HTTP request bodies
even prettier eldoc minibuffer message
add note-to-midi function
bugfix for note-to-midi
bugfixes for eldoc string echoing
add subtonic to chord syms list
add precomp header/footer to cairo lib
add precomp header/footer to jansson lib
Merge branch 'master' into nodevice-audio

* master:
  add precomp header/footer to jansson lib
  add precomp header/footer to cairo lib
  add subtonic to chord syms list
  bugfixes for eldoc string echoing
  bugfix for note-to-midi
  add note-to-midi function
  even prettier eldoc minibuffer message
  improvements to printing HTTP request bodies
  add setenv & unsetenv
  add sys:get-env