fix: first time uploadMessage called with undefined as parameter (#204)
fix: first time uploadMessage called with undefined as parameter (#204)

* fix: first time uploadMessage called with undefined as parameter

- During uploading DICOMs the first time the function is called with
  no parameter -> this leads to the whole upload to be crashing

* Write the function shorter...

OHIF/Viewers,OHIF/Viewers,OHIF/Viewers