Remove file texture loading (since we can just use file URLs), don't add alpha
channels for opaque textures (and note when textures with alpha channels are
entirely opaque), enforce a maximum texture size of 1024 by 1024.
allow Agents to microphone audio from Sound objects
changes to bot.js for new Agent microphone audio
Merge pull request #2391 from ey6es/master

Remove file texture loading (since we can just use file URLs), don't add...
Merge pull request #2392 from birarda/audio-scaling

allow Agents to send microphone audio using Sound objects
fix crash in bot.js with incorrect playSound
Merge pull request #2394 from birarda/master

fix bot.js crash