[NINJS] [FORMATTER]: render embeds
[NINJS] [FORMATTER]: render embeds

when body_html was regenerated, embed were discarded, this patch fixes
it.
Also body_html is not overwritten anymore if there is no annotation to
render.

fixes SDFID-214

hlmnrmr/superdesk-core,superdesk/superdesk-core,petrjasek/superdesk-core,superdesk/superdesk-core,petrjasek/superdesk-core,ioanpocol/superdesk-core,mugurrus/superdesk-core,mdhaman/superdesk-core,superdesk/superdesk-core,petrjasek/superdesk-core,hlmnrmr/superdesk-core,mdhaman/superdesk-core,petrjasek/superdesk-core,mugurrus/superdesk-core,mdhaman/superdesk-core,superdesk/superdesk-core,ioanpocol/superdesk-core,mugurrus/superdesk-core,ioanpocol/superdesk-core