upload source to mapbox.com after export ref #472
Merge branch 'master' into direct-upload
use progress-stream for reporting #472
remove get.stats
Merge branch 'master' into direct-upload

Conflicts:
	package.json
Back to progress-stream branch of tilelive.
Back to stop event.
Add task API lib.
- Move source mbtiles export to source lib
- Use task API to enforce one-at-a-time export jobs
- Update export template to expect task format
Omit fields that change across platforms in source export fixture.
Remove 'read' stream property from Task object and use only progress stream.
Test that unpipe is called on task.del().
Merge pull request #492 from mapbox/direct-upload-taskapi

Direct upload task API
Merge branch 'master' into direct-upload

Conflicts:
	lib/tm.js
	test/tm.test.js
Merge branch 'master' into direct-upload

Conflicts:
	index.js
upload returns a stream object
merge conflict
split export template up
improve model reset + ui updating
handle source.upload and res correctly