Fixes in 2019/ciura + update to bugs.md

Fixed scripts to use LC_ALL=C. This was necessary especially for de.sh
as the tr invocation had invalid bytes. Similar requirement was in
getwords.sh. But since I changed the one I decided to change the others
too.

I note that both before and after the fix the alternative languages do
not work under macOS or fedora linux. I don't know if this is the wrong
locale (the author does suggest UTF-8) or the dictionary or something
else but I noted it anyway.

I added this latter problem to bugs.md. Whilst at it I added some notes
and fixes to bugs.md.

2019/ciura/de.sh

@@ -1,3 +1,3 @@
 #!/usr/bin/env bash
 set -x
-./getwords.sh de | tr A-ZÄÖÜ a-zäöü | grep .. | ./prog aäbcdefghijklmnoöpqrsßtuüvwxyz
+LC_ALL=C ./getwords.sh de | LC_ALL=C tr '[:lower:]' '[:upper:]'  | LC_ALL=C grep .. | LC_ALL=C ./prog aäbcdefghijklmnoöpqrsßtuüvwxyz