Initial commit of watchdog usage.
Get preprocessors working with watchdog.
Modularize dev server observers into file_watchers.
Rename watchers -> observers.
Stream Compiler output instead of blocking.
Adjust Closure Compiler output.
Add pyinstaller to requirements.txt to make sure we use the virtualenv's pyinstaller when freezing.
Improve route matching. Fix up file watchers. Improve error page.
Slight tweak to error page.
Merge remote-tracking branch 'upstream/master'