[tx-robot] updated from transifex
SyncEngine: Handle 503 condition as soft error to properly handle etags.

Otherwise the ETags could be removed from the db and cause file
deletes.
ownSql: Don't set busy timeout on bad object
ownSql: Also mention filename
[tx-robot] updated from transifex
CheckServerJob: Guard again null reply

Lucia had reported a crash in this function
Windows Shell Integration: refresh the cache on UPDATE_VIEW

Attempt to fix #2383
Propagator:  report error when deleting directories

Will help to understand why a directory cannot be removed

Will help for #2348
Add missing license headers

Part of #2068
tests: make t1.pl work on jenkins, for that disable a size compare.
tests: exit t5.pl if running against ownCloud 6

t5.pl checks the environment variable SERVER_VERSION and if that equals
"owncloud6" it bails out after a check of the sharing ocs api.