Add missing files to 2015/endoh3

After emailing Yusuke he provided me with the missing files which I have
added to the repo. I removed this part from the thanks (I had noted that
there were some files missing) and removed the entry from the bugs.md
file.

Yusuke offered a hint and through this I noticed the main[] in the
README.md (I haven't yet looked at year 2015 in detail). It is what
generates the fun.tar.gz file (which is now in the .gitignore file as
the files within - except for the README.markdown there - are now in the
repo). I put this code in fun.c and added a rule to the Makefile to
build it (and it is built by default with make all). I also added to the
Makefile the rule to build (also by default) bf2pdp11.c. The README.md
notes how to use fun.c but it does not show how to use bf2pdp11 as I'm
not sure of the main use yet (I guess brainfuck to pdp11 which might be
useful with the brainfuck files added but that's all I can guess at this
time).

bugs.md

@@ -367,7 +367,7 @@ something was noted by the author, the judges, a consequence of earlier
 requirements for winning entries or the purpose was to do something that might
 appear to be buggy. An example of system specific entries:
 
-[1984/mullender](1984/mullender/mullender.c) (see below and the [faq](/faq.md)
+[1984/mullender](1984/mullender/mullender.c) (see below and the [FAQ](/faq.md)
 for a version that works in modern systems) is very system specific and was
 before system specific winning entries were discouraged. This is an all time
 personal favourite of Landon Curt Noll. Run the alternate code to understand why
@@ -1858,19 +1858,6 @@ is not. Again see his README.md for details!
 
 # 2015
 
-## [2015/endoh3](2015/endoh3/prog.c) ([README.md](2015/endoh3/README.md))
-## STATUS: missing files - please provide them
-
-With Yusuke's analysis of his entry which can be found
-[here](https://mame-github-io.translate.goog/ioccc-ja-spoilers/2015/endoh3.html?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp)
-he shows a tarball with source files that work with his entry, a mock emulator
-for [1984/mullender](1984/mullender/mullender.c). Unfortunately he does not have
-the tarball available for download and only showed a few (which
-[Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) added to the repo).
-
-Cody has his email and WILL be contacting him in time but we note it here anyway
-for now.
-
 
 # 2018