DDF-774 - Added Update Application webservice and update modal.

-Added a base modal class to the admin ui project.
-Created Update Modal to the UI.
-Created new method on the ApplicationUploadEndPoint class to handle the
update file upload call.  Should be similar to the create.
-Added support methods to the ApplicationFileInstaller that will extract a
version/applicatoinName from a zipfile based on the features.xml file
contianed within it.
Use HttpStatus.SC_UNSUPPORTED_MEDIA_TYPE rather than the magic number.