Invalid diff link on commit message emails for new files

Emails that we generate for commits have a handy diff link at bottom. alas, the syntax for that link has to be different for a new file. this patch implements that. requires a visit to the config file. set 'logs_cvsurls_initial' to the same as logs_cvsurls but omit the whole querystring ... i can't test this, but it should work :)