[ENH]Add {{pageid}} also as a new wiki argument variable (needed for custom scripts with PluginR reusing content generated in the default cached folder).

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@49114 b456876b-0849-0410-b77d-98878d47e9d5
[ENH]Add {{domainslash_if_multitiki}} also as a new wiki argument variable, since that is going to be one more needed to make cache-dir-paths in custom scripts work in both normal  or in multitiki environments


git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@49115 b456876b-0849-0410-b77d-98878d47e9d5