added './build' directory as default out-of-source build structure for cmake; all files inside are ignored by the .gitignore rules; populate the folder by running 'cmake ..' inside it
added CMakeLists.txt for ni and tlu producers and executables -- will only be optionaly build when BUILD_[dir] is set; made build of main executables optional via BUILD_main option
added CMake script for building GUI using Qt; in principle, both Qt4 and Qt5 should work, Qt5 build script not tested though
added cmake scripts for gui, onlinemon and remaining processors; added FindROOT.cmake script