* Rename param for consistency
* Move media loading functionality into DictionaryImporterMediaLoader
* Create test class for media loading
* Remove unnecessary Blob/Image/URL functionality
* Fix content security policy for images
* Add createBlobFromBase64Content to MediaUtil
* Update MediaLoader to use MediaUtil
* Use blob URLs when importing dictionaries
* Update VM's URL to support createObjectURL and revokeObjectURL
* Fix test