move fix thanks a file, update top level html links, rename CONTRIBUTING.md

The fix thank you's have been moved from `README.md` to
`thanks-for-fixes.md`.

**WARNING**: Some mistakes may have been made in doing this.
We presume later changes by others will correct any issues.

The `CONTRIBUTING.md` was renamed `how-to-enter.md`.

A 3rd line of links was added to top level html such as
`contact.html`, `index.html`, `judges.html`, `winners.html`,
and `years.html`.

Improved blank line use in a number (but not all) `README.md` files.

2000/natori/README.md

@@ -6,16 +6,13 @@ Rigakubu 7-goukan 311
 Hongou 7-3-1, Bunkyou-ku, Tokyo
 Japan
 
+
 ## To build:
 
 ```sh
 make
 ```
 
-[Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) fixed this for modern
-compilers. Depending on the compiler it would either segfault when run or not
-compile at all (gcc and clang respectively). Thank you Cody for your assistance!
-
 
 ## To run:
 
@@ -23,19 +20,20 @@ compile at all (gcc and clang respectively). Thank you Cody for your assistance!
 ./natori
 ```
 
+
 ## Try:
 
 ```sh
 echo "Do or do not. There is no try."
 ```
 
+
 ### Alternate code:
 
 The author noted that those in the southern hemisphere might want to change
-`acos(l/2)` into `acos(-l/2)`. Cody went ahead and made an alt version to do
-this.
+`acos(l/2)` into `acos(-l/2)`. 
 
-To run:
+To run the alternate code that supports the southern hemisphere:
 
 ```sh
 make alt
@@ -43,6 +41,7 @@ make alt
 
 Use `natori.alt` as you would `natori`.
 
+
 ## Judges' remarks:
 
 Here is a nice compact program that changes with the phase of the moon.
@@ -54,6 +53,7 @@ own non-traditional prototype for main().  We have had uglify this
 program in order to try and prevent C compilers form failing to
 compile due to the unusual arg types of the main() function.
 
+
 ## Author's remarks:
 
 This program outputs a rough image of the moon in its current phase.
@@ -63,6 +63,7 @@ The main obfuscation of this entry is its complicated double recursion
 People living in the southern hemisphere may want to change `acos(l/2)`
 into `acos(-l/2)`.
 
+
 ## Copyright and CC BY-SA 4.0 License:
 
 This file is Copyright (c) 2023 by Landon Curt Noll.  All Rights Reserved.