Added quote_plus() and unquote_plus(), to do space/plus substitutions

for form field values.
Also corrected substitution example (the original changed the spelling
of "conolly" to "connolly" :).

Doc/lib/liburllib.tex

@@ -59,7 +59,12 @@ Letters, digits, and the characters ``\code{_,.-}'' are never quoted.
 The optional \var{addsafe} parameter specifies additional characters
 that should not be quoted --- its default value is \code{'/'}.
 
-Example: \code{quote('/\~conolly/')} yields \code{'/\%7econnolly/'}.
+Example: \code{quote('/\~connolly/')} yields \code{'/\%7econnolly/'}.
+\end{funcdesc}
+
+\begin{funcdesc}{quote_plus}{string\optional{\, addsafe}}
+Like \code{quote()}, but also replaces spaces by plus signs, as
+required for quoting HTML form values.
 \end{funcdesc}
 
 \begin{funcdesc}{unquote}{string}
@@ -68,6 +73,11 @@ Replace \samp{\%xx} escapes by their single-character equivalent.
 Example: \code{unquote('/\%7Econnolly/')} yields \code{'/\~connolly/'}.
 \end{funcdesc}
 
+\begin{funcdesc}{unquote_plus}{string}
+Like \code{unquote()}, but also replaces plus signs by spaces, as
+required for unquoting HTML form values.
+\end{funcdesc}
+
 Restrictions:
 
 \begin{itemize}

Doc/liburllib.tex

@@ -59,7 +59,12 @@ Letters, digits, and the characters ``\code{_,.-}'' are never quoted.
 The optional \var{addsafe} parameter specifies additional characters
 that should not be quoted --- its default value is \code{'/'}.
 
-Example: \code{quote('/\~conolly/')} yields \code{'/\%7econnolly/'}.
+Example: \code{quote('/\~connolly/')} yields \code{'/\%7econnolly/'}.
+\end{funcdesc}
+
+\begin{funcdesc}{quote_plus}{string\optional{\, addsafe}}
+Like \code{quote()}, but also replaces spaces by plus signs, as
+required for quoting HTML form values.
 \end{funcdesc}
 
 \begin{funcdesc}{unquote}{string}
@@ -68,6 +73,11 @@ Replace \samp{\%xx} escapes by their single-character equivalent.
 Example: \code{unquote('/\%7Econnolly/')} yields \code{'/\~connolly/'}.
 \end{funcdesc}
 
+\begin{funcdesc}{unquote_plus}{string}
+Like \code{unquote()}, but also replaces plus signs by spaces, as
+required for unquoting HTML form values.
+\end{funcdesc}
+
 Restrictions:
 
 \begin{itemize}