Merge pull request #326 from MSOpenTech/development

Bugfixing
Merge pull request #327 from MSOpenTech/development

Adds a reference for a new RequestModifierExtensions class and removes a...
Correct MPDHelper.js name in Gruntfile.js

The wrong name will result in Task "jasmine:tests" failed:
TypeError: 'undefined' is not an object (evaluating 'mpdHelper.getAdaptationWithSegmentTemplate'
Merge pull request #329 from qjia7/MpdHelper

Correct MPDHelper.js name in Gruntfile.js