Fix consistency in menus and pages

In some pages at the top it had 'and' but in the menu it had instead a
'&'. The menus (JavaScript and otherwise) now has 'and' to match the
pages. The file nojs-menu.html has been checked for broken links and
indeed one at least was fixed. Very few top level html files need to be
checked now. Some that are entirely generated should be okay but links
will still be checked to be sure.

Some cases of '(Mis)features' from the previous commit were also
corrected to '(mis)features' as this is also part of menu and page
consistency.

The files markdown.{md,html} have had the menus updated too but there
are some other changes that were works in progress. This file is not
thus completed but will be sometime soon.

markdown.md

@@ -1,21 +1,21 @@
 # IOCCC markdown best practices
 
 The IOCCC makes extensive use of [markdown](https://daringfireball.net/projects/markdown/).
-For example, we [submitting to the IOCCC](faq.html#submit), we have people
-to submit remarks about entry in markdown format.  Every
+For example, when [submitting to the IOCCC](faq.html#submit), we have people
+submit remarks about their entry in markdown format.  Every
 [winning IOCCC entry](years.html) uses a `README.md` markdown file
 as the basis for forming the `index.html` web page for that entry.
 All generated HTML pages on the [Official IOCCC website](https://www.ioccc.org/index.html)
 start with some markdown content.
 
 See the [markdown syntax](https://www.markdownguide.org/basic-syntax) guide.
-See also [CommonMark Spec](https://spec.commonmark.org/current/).
+See also the [CommonMark Spec](https://spec.commonmark.org/current/).
 
 Nevertheless, the IOCCC does have certain practices that we ask authors to follow.
-Some these relate to use of markdown directly, others relate to injecting HTML
+Some of these relate to use of markdown directly and others relate to injecting HTML
 into the markdown file.
 
-In particular there are things we ask people to please do **NOT** use in
+In particular there are things we ask people to please **NOT** use in
 markdown files for the IOCCC:
 
 
@@ -24,7 +24,7 @@ markdown files for the IOCCC:
 Please do **NOT** use the HTML construct:
 
 ```
-    <a name="string">...</a>                                  <=== no thank you
+    <a name="string">...</a>                                  <!-- no thank you -->
 ```
 
 as those are **NOT** part of the HTML 5 standard.
@@ -46,10 +46,10 @@ id="string">...</div>`.
 For example:
 
 ```
-    # <div id="string">THIS WILL NOT WORK!</div>              <=== this will not work
+    # <div id="string">THIS WILL NOT WORK!</div>              <!-- this will not work -->
 ```
 
-For things like headings, you have to surround them as in:
+For things like headings, you have to surround them, as in:
 
 ```
     <div id="string">
@@ -61,13 +61,13 @@ While some browsers will still recognize the HTML construct `<a
 name="string">...</a>`, it is possible they might NOT in the future.
 
 
-## Please do NOT use the `<strike>` nor `<s>` HTML element
+## Please do NOT use the `<strike>` or `<s>` HTML element
 
-Please NOT use the obsolete `<strike>` nor `<s>` (<del> _strikeout_ </del>) HTML elements:
+Please NOT use the obsolete `<strike>` or `<s>` (<del>_strikeout_</del>) HTML elements:
 
 ```
-    <strike>...</strike>                                      <=== no thank you
-    <s>...</s>                                                <=== no thank you
+    <strike>...</strike>                                      <!-- no thank you -->
+    <s>...</s>                                                <!-- no thank you -->
 ```
 
 Use instead:
@@ -82,7 +82,7 @@ Use instead:
 Please NOT use the obsolete `<u>` (<ins>_underline_</ins>) HTML element:
 
 ```
-    <u>...</u>                                                <=== no thank you
+    <u>...</u>                                                <!-- no thank you -->
 ```
 
 Use instead:
@@ -97,7 +97,7 @@ Use instead:
 Please do **NOT** use the obsolete `<tt>` (<span style="font-family: monospace;">_teletype_</span>) HTML element:
 
 ```
-    <tt>The obsolete tt element is obsolete</tt>              <=== no thank you
+    <tt>The obsolete tt element is obsolete</tt>              <!-- no thank you -->
 ```
 
 Instead use either a monospaced span:
@@ -119,8 +119,7 @@ Please do **NOT** start code blocks at the left-hand edge.
 
 ````
 ```
-This code block                                               <=== no thank you
-is NOT indented
+This code block is NOT indented                   <!-- no thank you -->
 ```
 ````