Add missing MIDI files to 2020/otterness

These files in particular were previously to be downloaded prior to use
of the program (or try section). These files have now been downloaded
and added to the repo.

Format/typo check README.md file.

Updated bugs.md with features/limitations.

bugs.md

@@ -3617,6 +3617,32 @@ exactly 16 bits per sample, but it allows any sample rate and any number of
 audio channels.
 
 
+## 2020 otterness
+
+### STATUS: INABIAF - please **DO NOT** fix
+### Source code: [2020/otterness/prog.c](2020/otterness/prog.c)
+### Information: [2020/otterness/README.md](2020/otterness/README.md)
+
+The author listed the following limitations:
+
+1. The program does not support MIDI files over 4 MB (specifically, it will
+not take input files larger than `2^22 - 1` bytes).  This is unlikely to be a
+big limitation in practice, since even lengthy MIDIs are rarely over a
+couple hundred KB.
+
+2. Not all MIDIs set (or *correctly* set) their timing information, which will
+lead to the tempo of the drum beat not matching the track.  This will be
+especially true for "live performance" .mid files.
+
+3. There may be some types of MIDI messages that the program is unable to
+correctly parse, but I have rarely seen this in practice.  The largest
+cause of program failures, in my experience, has been Limitation 2.
+
+See also the [Program error
+codes](/2020/otterness/README.md#program-error-codes) written by the author
+which lists some other conditions which should be considered features, not bugs.
+
+
 # 2021
 
 There was no IOCCC in 2021.
@@ -3632,25 +3658,6 @@ There was no IOCCC in 2022.
 There was no IOCCC in 2023.
 
 
-# Final words
-
-We hope this document was of use to you in determining which entries are known
-to have a problem, what entries are known to have features that are not bugs and
-so on. We also thank you for going through this document and, if you propose any
-fixes via a [GitHub pull
-request](https://github.com/ioccc-src/temp-test-ioccc/pulls) or otherwise, we
-thank you as well for the help! We will happily add you to the
-[thanks](/thanks-for-help.md) file.
-
-There was no IOCCC in these years.
-
-# 2023
-
-Probably there will be no IOCCC in 2023 but we do hope to at least run the
-IOCCCMOCK contest this year. This depends entirely on the work in this repo
-and the [mkiocccentry](https://github.com/ioccc-src/mkiocccentry) being
-completed.
-
 # Final words
 
 We hope this document was of use to you in determining which entries are known