Originally a spike to see if doing the app without rails would work and became a spike on getting user login working on Firebase

* Removing rails as it's not needed and was causing problems with Safari and Midi.js
* Removing many of the instruments as there were too many
*
Revert "Originally a spike to see if doing the app without rails would work and became a spike on getting user login working on Firebase"

This reverts commit 2adf729a7dc134f3195a33839b5b8d997a79f3c2.
Removing rails

* Rails is unnecessary since all code is javascript/html/css, and it's causing problems with running the app in Safari
Merge pull request #15 from artfoundry/remove-rails

Remove rails