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.

2015/burton/road.to.obscurity.md

@@ -17,11 +17,11 @@ were added over time.
 dance began (this is called foreshadowing):
 
 ```
-()		forced precedence
-- ~ ?		unary minus, compl, byteswap
-* / % & << >>	mul, div, mod, bitand, shift: left, right
-+ - | ^		add, sub, bitor, xor
-NUM		0-9
+    ()		forced precedence
+    - ~ ?		unary minus, compl, byteswap
+    * / % & << >>	mul, div, mod, bitand, shift: left, right
+    + - | ^		add, sub, bitor, xor
+    NUM		0-9
 ```
 
 This seemed like a reasonable candidate to experiment with obfuscation; perhaps
@@ -33,41 +33,41 @@ it might yield good results.
 The algorithm was and is rather straightforward:
 
 ```
-expr() {
-	n = term()
-	t = token()
-	if (t == ADD) return n += expr()
-	if (t == SUB) return n -= expr()
-	if (t == BOR) return n |= expr()
-	if (t == XOR) return n ^= expr()
-	ungettoken(t)
-	return n
-}
-term() {
-	n = factor()
-	t = token()
-	if (t == MUL) return n *= term()
-	if (t == DIV) return n /= term()
-	if (t == AND) return n &= term()
-	if (t == RSH) return n >> term()
-	if (t == LSH) return n << term()
-	ungettoken(t)
-	return n
-}
-factor() {
-	t = token()
-	if (t == LPAREN) {
-		n = expr()
-		if token() == RPAREN
-			return n
-		error()
-	}
-	if (t == SUB) return -factor()
-	if (t == CMP) return ~factor()
-	if (t == QUE) return byteswap(factor())
-	if (t == DIG) return strtol()
-	error()
-}
+    expr() {
+	    n = term()
+	    t = token()
+	    if (t == ADD) return n += expr()
+	    if (t == SUB) return n -= expr()
+	    if (t == BOR) return n |= expr()
+	    if (t == XOR) return n ^= expr()
+	    ungettoken(t)
+	    return n
+    }
+    term() {
+	    n = factor()
+	    t = token()
+	    if (t == MUL) return n *= term()
+	    if (t == DIV) return n /= term()
+	    if (t == AND) return n &= term()
+	    if (t == RSH) return n >> term()
+	    if (t == LSH) return n << term()
+	    ungettoken(t)
+	    return n
+    }
+    factor() {
+	    t = token()
+	    if (t == LPAREN) {
+		    n = expr()
+		    if token() == RPAREN
+			    return n
+		    error()
+	    }
+	    if (t == SUB) return -factor()
+	    if (t == CMP) return ~factor()
+	    if (t == QUE) return byteswap(factor())
+	    if (t == DIG) return strtol()
+	    error()
+    }
 ```
 
 ## Obfuscation is a process