Be more specific about corner cases in the description of the $ RE syntax,

and include an example where the MULTILINE flag makes a real difference.

This closes SF bug #441600.

Doc/lib/libre.tex

@@ -96,10 +96,13 @@ specified, this matches any character including a newline.
 \item[\character{\^}] (Caret.)  Matches the start of the string, and in
 \constant{MULTILINE} mode also matches immediately after each newline.
 
-\item[\character{\$}] Matches the end of the string, and in
-\constant{MULTILINE} mode also matches before a newline.
-\regexp{foo} matches both 'foo' and 'foobar', while the regular
-expression \regexp{foo\$} matches only 'foo'.
+\item[\character{\$}] Matches the end of the string or just before the
+newline at the end of the string, and in \constant{MULTILINE} mode
+also matches before a newline.  \regexp{foo} matches both 'foo' and
+'foobar', while the regular expression \regexp{foo\$} matches only
+'foo'.  More interestingly, searching for \regexp{foo\e d} in
+'foo1\textbackslash nfoo2\textbackslash n' matches 'foo2' normally,
+but 'foo1' in \constant{MULTILINE} mode.
 
 \item[\character{*}] Causes the resulting RE to
 match 0 or more repetitions of the preceding RE, as many repetitions