FEAT: Ban command, save ops and banned ppl in files

TODO: fix many crashes...

src/commands/CommandBan.hpp

@@ -0,0 +1,9 @@
+#include "Command.hpp"
+
+class CommandBan : public Command {
+public:
+    CommandBan();
+
+    std::string execute(Minecraft& mc, Player& player, const std::vector<std::string>& args);
+    std::string help(Minecraft& mc);
+};