Support in RESTful WC plugin to return binary data uses non-standard mimetype
Case: SVY-6098
Support in RESTful WC plugin to return binary data uses non-standard mimetype 
Case: SVY-6098
Backport to 7.4.2
Inlined MimeTypes.getContentType (new public method in 8.0) to make it
work in v74
Case: SVY-6098