Use gulp/uglify for CSS/JS compilation
Add new gulp task to manually clean files instead of dangerously deleting them while they can be served
Use cleancss instead of less's built-in compression
Run the outer callback after the inner stream is finished, so the task sequence is accurately reported on the command line
Build JavaScript sourcemaps
Merge remote-tracking branch 'bitmap/gulp' into beta

* bitmap/gulp:
  Build JavaScript sourcemaps
  Run the outer callback after the inner stream is finished, so the task sequence is accurately reported on the command line
  Use cleancss instead of less's built-in compression
  Add new gulp task to manually clean files instead of dangerously deleting them while they can be served
  Use gulp/uglify for CSS/JS compilation
Add npm install to socket-deploy too.