Fix 1990/jaw/btoa script

This now lets the command in the judges' remarks:

    echo "Quartz glyph jocks vend, fix, BMW." | compress | ./btoa | ./jaw

not report just:

    oops
    oops

and instead it outputs data which suggests, I believe, that the program
is not buggy but instead the script had to have the 'xbtoa' changed to
'btoa'.

Updated bugs.md and thanks-for-fixes.md and README.md file too.

Other changes were made to thanks file as they are more appropriate than
in the README.md (of 1990/theorem) after the (once again sounding like
a broken record) vastly superior idea of the thanks file came up. This
addition here is unintentional; it was just already there but not ready
for committing as 1990/theorem/README.md was not yet ready. That file
will be committed today.

1990/jaw/README.md

@@ -17,17 +17,6 @@ make all
 ```
 
 
-### Bugs and (Mis)features:
-
-The current status of this entry is:
-
-```
-STATUS: known bug - please help us fix
-```
-
-For more detailed information see [1990 jaw in bugs.md](/bugs.md#1990-jaw).
-
-
 ### Try:
 
 To test the official C entry, one might try:
@@ -40,7 +29,7 @@ which should apply the identity transformation to a minimal holoalphabetic
 sentence.
 
 
-Also try:
+#### Also try:
 
 ```sh
 ./try.sh

1990/jaw/btoa

@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
-puts "xbtoa Begin"
+
+puts "btoa Begin"
 data = $<.read
 n, e, s, r = data.bytesize, 0, 0, 0
 (-n % 4).times { data << 0 }
@@ -9,4 +10,4 @@ end
 data.unpack("N*").flat_map do |v|
   v == 0 ? [?z.ord] : (0..4).map {|i| v / 85**(4 - i) % 85 + 33 }
 end.pack("C*").scan(/.{1,78}/) { puts $& }
-puts "xbtoa End N %d %x E %x S %x R %x" % [n, n, e, s, r]
+puts "btoa End N %d %x E %x S %x R %x" % [n, n, e, s, r]