Fix flexbox issues in Firefox (LT-277)

OHIFViewer/client/components/viewer/viewer.styl

@@ -1,14 +1,9 @@
 @import "{design}/app"
 
 #viewer
-  align-items: stretch
   background-color: black
-  display: flex
-  flex-flow: column wrap
   height: 100%
   width: 100%
-  margin: 0
-  padding: 0
 
 .loadingTextDiv
   color: $textSecondaryColor

Packages/lesiontracker/client/components/viewer/viewer.styl

@@ -1,15 +1,9 @@
 @import "{design}/app"
 
 #viewer
-  align-items: stretch
   background-color: black
-  display: flex
-  flex-flow: column wrap
   height: 100%
   width: 100%
-  margin: 0
-  padding: 0
-
 
 #imageViewerViewports
   .viewportContainer