Abort XHR properly in setCurrentTime
Fix the spec to pass the test.
Add test and null segementXhr in dispose
Remove event handlers in dispose.
Test that segmentXhr gets nulled out in dispose.
Add a test for removing event handlers
PR comment updates
remove unneeded media object
Change event handler test to be more generic
Merge pull request #156 from videojs/abortxhr

null out segmentXhr, remove event handlers on dispose