improved indentation and whitespace for markdown code blocks

All code blocks in markdown have been intended by at least 4 spaces.

We add `--tab-stop=8` to all `pandoc(1)` executions in order to set
a better tab stop indentation, especially for tab intended code blocks.

Changed `bin/pandoc-wrapper.sh` VERSION from "1.5.3 2024-03-26"
to "1.6 2024-03-31".

Fixed `1991/brnstnd/sorta.README.md` so that the sorta code
is code blocks.

Removed unneeded paragraph group in copyright in `inc/footer.default.html`.

Fixed excess whitespace after list Author on entry `index.html` page.

Changed `bin/output-index-author.sh` VERSION from "1.5.2 2024-03-26"
to "1.6 2024-03-31".

Performed `make www` to perform the above and test under macOS.

TODO: Fix the problem of the initial line of code being extra intended.
TODO: Fix excess whitespace around code that is inline.

2018/anderson/README.md

@@ -1,7 +1,7 @@
 ## To build:
 
 ```sh
-make
+    make
 ```
 
 There is an alternate version of this entry. See [Alternate
@@ -11,14 +11,14 @@ code](#alternate-code) below for more details.
 ## To use:
 
 ```sh
-./prog < textfile
+    ./prog < textfile
 ```
 
 
 ## Try:
 
 ```sh
-./try.sh
+    ./try.sh
 ```
 
 
@@ -32,7 +32,7 @@ it was not the shape of the Roman V that we, or the compiler, didn't like.
 ### Alternate build:
 
 ```sh
-make alt
+    make alt
 ```
 
 
@@ -44,7 +44,7 @@ Use `prog.alt` as you would `prog` above.
 ### Alternate try:
 
 ```sh
-./try.alt.sh
+    ./try.alt.sh
 ```
 
 
@@ -59,7 +59,7 @@ down](http://en.wikipedia.org/wiki/River_%28typography%29)!
 ### Compiling the program:
 
 ```sh
-cc -Wall -Wextra -Wpedantic -O3 -std=c11 prog.c -o prog
+    cc -Wall -Wextra -Wpedantic -O3 -std=c11 prog.c -o prog
 ```
 
 Also works with a standard of C99, but C90/C89 will not compile due to