DEN-13966 Improvement: Export individual log files - Used the stashed file copy by by chunk algorithm which I wrote before for exporting the log files. - It will help later to have more control over copying files. - Added all the signal/slots for Logger, ApplicationController, GuiController, GuiView and the QML side. - Implemented the Export Selection Map on the C++ side to be used for individual log file selection (insert, delete, select, remove/Clear). - Added percent update for the current exporting file. (not implemented on UI, due to some issues)