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/ciura/README.md

@@ -1,7 +1,7 @@
 ## To build:
 
 ```sh
-make
+    make
 ```
 
 There is an alternate version that lacks a useful bug fix. See [Alternate
@@ -12,14 +12,14 @@ below for more details.
 ## To use:
 
 ```sh
-./prog < text
+    ./prog < text
 ```
 
 
 ## Try:
 
 ```sh
-./try.sh
+    ./try.sh
 ```
 
 
@@ -33,7 +33,7 @@ useful bug fix.
 ### Alternate build:
 
 ```sh
-make alt
+    make alt
 ```
 
 
@@ -45,7 +45,7 @@ Use `prog.alt` as you would `prog` above.
 ### Alternate try:
 
 ```sh
-./try.alt.sh
+    ./try.alt.sh
 ```
 
 Do you spot the fix by running both [try.sh](try.sh) and