Add bank focus string removal

CMakeLists.txt

src/config.h

src/lns/lns.cpp

src/lns/modification/route/remove_route.cpp

...n/bank_focus_string_removal/bank_focus_string_removal.cpp

...ion/bank_focus_string_removal/bank_focus_string_removal.h

src/lns/operators/destruction/string_removal.cpp

src/lns/solution/solution.cpp

src/mains/main.cpp