#26 file preview REST proxy and template for for text/xml
#26 text and image viewer
#26 PDF viewer w/ local storage and REST service
#26 file synchronization indicator (still bad CSS), improved sync algo to avoid failures on contraint violation, possibility push local file manually, CMIS connector API improved for errors, code/logs cleanup
#26 file syncing CSS; improved local to cloud sync to reduce number of updates for single file; improved error handling with JS client