fixed false memory leak warning when compiled in debug mode (Windows only)

git-svn-id: svn://svn.code.sf.net/p/nzbget/code/trunk@1169 b1b436ca-2b18-4f33-ab5d-510789358d54
fixed: unrar may sometimes fail with message "no files to extract"

git-svn-id: svn://svn.code.sf.net/p/nzbget/code/trunk@1171 b1b436ca-2b18-4f33-ab5d-510789358d54
actions for history items can now be performed for multiple (selected) records: post-process again, download again, mark as good, mark as bad; extended RPC-API method "editqueue": for history-records of type "URL" the action "HistoryRedownload" can now be used as synonym to "HistoryReturn" (makes it easier to redownload multiple items of different types (URL and NZB) with one API call)

git-svn-id: svn://svn.code.sf.net/p/nzbget/code/trunk@1172 b1b436ca-2b18-4f33-ab5d-510789358d54