Added the possibility to specify own copy-of names for files as an alternative to the ones defined in translation files (CH-182). Changed default copy-of names in english and polish translations so that always start with %name instead of word "Copy".
Modified updates checking: - added new option to let user decide if he wants secure connection or not (with autodetection), - fixed error messages being displayed incorrectly or empty, - fixed ability to re-check for updates after failure. (CH-241).