This removes around megabyte from the binary, so a stripped -Og binary
went from 4.0 megabytes to 2.9 megabytes, and an unstripped -O0 binary
went from 8.1 megabytes to 7.1 megabytes, which means I can now finally
upload an unstripped -O0 binary to Discord without having to give money
to Discord for their dumb Nitro thing or whatever.
Looks like coins were basically a scrapped mechanic, although I'm not
sure what these attributes were for. I guess counting the number of
coins in each room? But why, when you can just make a function to count
them automatically? Whatever.
map.contents always has 1200 tiles in it, there's no reason it should be
a vector.
This is a big commit because it requires changing all the level classes
to return a pointer to an array instead of returning a vector. Which
took a while for me to figure out, but eventually I did it. I tested to
make sure and there's no problems.