Originally the page said:
> No other escaping takes place in balanced strings.
...but in the course of a general readability rewrite (56287da) this was
changed to:
> Characters may be escaped in the same manner as those for quoted strings.
...which is not actually true; probably this change made it in because there
were a lot of good changes in those commits and we didn't read them all closely
enough.
Now the documentation is correct again, and I've added some examples covering
the problems people occasionally ask about (see #2760).
Fixes issue #2377 by removing the ability to escape backticks in backticks in compliance with asciidoc's behaviour. Adjusted hooks.asciidoc, keys.asciidoc, and command-parsing.asciidoc to match accordingly.