Improve 2019/karns/try.sh, force -O0

The try.sh script now prompts for input rather than just sleep for 2
seconds.

The README.md file has been format/typo checked.

Added issues reported by the author to bugs.md.

Force disable optimiser as the program doesn't work in some cases with
it enabled. If I recall correctly it crashed in some cases, something
the author noted happens sometimes (it is unknown if it is because they
had it enabled or if it was something else but I have not experienced a
crash since then).

bugs.md

@@ -3466,6 +3466,32 @@ As a backtrace quine this entry is **SUPPOSED to segfault** so this should not b
 touched either.
 
 
+## 2019 karns
+
+### STATUS: INABIAF - please **DO NOT** fix
+### Source code: [2019/karns/prog.c](2019/karns/prog.c)
+### Information: [2019/karns/README.md](2019/karns/README.md)
+
+The author stated the following:
+
+---
+
+- The program must be ran in a terminal that supports ANSI escape codes for
+moving the cursor and changing colors.
+- Segfaults happen sometimes.
+- I don't know what memory management there is, if any.
+- The program will not compile by an ANSI C compiler: it uses for loops, and
+it uses C++ style comments. It should compile cleanly using a C99 standard.
+- Breadth first search is slow (and very slow on certain maps), but my A star
+version of this program is too big.
+- Lots of extra whitespace may be needed if you want to feed in an arbitrary
+file.
+- It fails to compile on GCC sometimes (according to a friend of mine, I've
+not encountered this myself).
+- The program could be obfuscated much further.
+- The program contains some unused code and data.
+
+
 ## 2019 poikola
 
 ### STATUS: INABIAF - please **DO NOT** fix