-- apply request headers provided by corresponding caller to the HTTP/WebDAV request
needed for our update service 

i118923 - OS/2 port: improve r1299242/r1299759, quotes must be removed also in perl parameter, forgot to test a clean build before, last commit regarding this issue, promised :-).

- found during testing of insertion of linked images from HTTP/HTTPS servers

-- use transfer-encoding 'chunked' on HTTPS
-- switch transfer-encoding between 'chunked' and none on 413 HTTP status code
-- refactoring
-- improve user experience of certification dialog - only shown once

118012 - methods <ScBroadcastAreaSlot::AreaBroadcast(..)> and <ScBroadcastAreaSlot::AreaBroadcastInRange(..)>

adapt stl-container interation in order to avoid destroyed iterators during iteration.