Make plugin options accessible by xhr helper
add responseType option to xhr helper
convert segmentXHR to use xhr helper
Options object may not contain a url.
move startTime before xhr call
fix 'selects a playlist after segment downloads'
fix 'moves to next segment if network error'
Revert "fix 'selects a playlist after segment downloads'"

This reverts commit 3bccfa73915d1a547367b05aa317565d7d0c7535.
make sure that options is an object
Use sinon fakeXmlHttpRequest.
Change out the custom synchronous XHR to use sinon's fake XHR.
This allows to decide exactly when to respond to XHRs.
Add sinon to jshintrc. Fix jshint errors.
Also, remove resetting setTimeout as it's already being done in
setup/teardown.
code review comments
Switch to use npm sinon
Merge branch 'feature/live-um' into withcredentials

Conflicts:
	package.json
move sinon to dev deps
Add test for withCredentials option
Merge branch 'master' into withcredentials

Conflicts:
	package.json
	test/.jshintrc
open XHR before setting properties on it
Merge branch 'master' into withcredentials
Merge branch 'master' into withcredentials