* class.jam; Use new "::" syntax.
* doc.jam; Change comment parsing to keep leading whitespaces.
* doc.jam; Fix problem when a rule's argument has the same name as an inner rule.
* print.jam; Implement ReST syntax of "::" to indicate preformatted text. All forms of the ReST syntax are supported, and the additional form of a preformated paragraph with the first line as "::".
[SVN r16244]