Debug macro and stack trace

One way you can start debugging your code is by using #define to create a debugging macro, which we can activate by passing a flag into the Emscripten compiler. However, this will resolve to nothing if we don't pass that flag. Macros are easy to add, and we can create a call that prints a line if we are running with our debug flag, but will not slow down performance if we aren't. If you are not familiar with preprocessor commands, they are commands that are issued to the compiler that evaluate while the code is compiled instead of at runtime. For instance, if I used a #ifdef PRINT_ME command, the line of code would only be compiled into our source code if the PRINT_ME macro is defined either with a #define PRINT_ME macro on a line earlier in the code, or if we compiled the source with the -DPRINT_ME flag passed into the compiler when we ran...