Remove the cross-domain phrase from README.md

The part about `Cross-domain Ajax and Flash` from the `README.md` file
isn't accurate, as by default:

 * the `crossdomain.xml` file doesn't grant a web client — such as Adobe
   Flash Player, Adobe Reader, etc. — permission to handle data across
   multiple domains

 * the Apache server configs, do not allow cross-origin access to all
   resources, unless the user enables that behavior

README.md

@@ -45,7 +45,6 @@ Choose one of the following options:
 * An optimized Google Analytics snippet.
 * Apache server caching, compression, and other configuration defaults for
   Grade-A performance.
-* Cross-domain Ajax and Flash.
 * "Delete-key friendly." Easy to strip out parts you don't need.
 * Extensive inline and accompanying documentation.
 

dist/doc/misc.md

@@ -166,7 +166,7 @@ If you want to disallow certain pages you will need to specify the path in a
 `Disallow` directive (e.g.: `Disallow: /path`) or, if you want to disallow
 crawling of all content, use `Disallow: /`.
 
-The '/robots.txt' file is not intended for access control, so don't try to
+The `/robots.txt` file is not intended for access control, so don't try to
 use it as such. Think of it as a "No Entry" sign, rather than a locked door.
 URLs disallowed by the `robots.txt` file might still be indexed without being
 crawled, and the content from within the `robots.txt` file can be viewed by

src/doc/misc.md

@@ -166,7 +166,7 @@ If you want to disallow certain pages you will need to specify the path in a
 `Disallow` directive (e.g.: `Disallow: /path`) or, if you want to disallow
 crawling of all content, use `Disallow: /`.
 
-The '/robots.txt' file is not intended for access control, so don't try to
+The `/robots.txt` file is not intended for access control, so don't try to
 use it as such. Think of it as a "No Entry" sign, rather than a locked door.
 URLs disallowed by the `robots.txt` file might still be indexed without being
 crawled, and the content from within the `robots.txt` file can be viewed by