Added suggestions for misspelled variable and function names.

I have added the feature that the compiler suggests corrections for mistyped variable and function names, using the Longest Common Subsequence algorithm. I have also improved the documentation a bit. For executable files, again, look into v1.4.3 for Linux executable files and v1.4.2 for other executable files. Producing executable files for various operating systems is a tedious job, I hope you understand.

UPDATE: Due to the weird issue that appears to occur only under some compilers on Windows, to make sure compiling my program is not the problem, I have decided to add some executable files here. Windows executable files are produced here using the 64-bit TDM-GCC. I cannot produce Linux executable files because Docker seems to have stopped working on my computer.

UPDATE: I have managed to run Docker again on my computer and produce Linux executable files.

UPDATE: For a reason that escapes me (given what I know, it should not even be possible), on my old computer with 32-bit Windows XP, the FreeDOS executable produced by DJGPP runs around 2 times faster than the 32-bit Windows executable produced by TDM-GCC. I asked a Quora question about this. So, if the 32-bit Windows executable runs too slow on your computer, try the FreeDOS executable. I have no idea how it can be, but it is actually faster.