'tag' command works once more
'source ~/' shows the matches
fdopen checks whether the file exists, and throws a more-readable error if it doesn't
'help' work if the current document is a XULDocument (it shows the help in a new tab)
the extension id has changed to a more readable string. any older versions of vimperator MUST be uninstalled, otherwise there will be 2 versions of the extension in the addons list.