[BRLTTY] Cut and paste creates clipboard bugs

[Samuel Thibault]

Re,

Dave, we have an issue with AtSpi2 when running it with -N (which should
usually be the case): since the BrlAPI server is then not running, 

registerReportListener(REPORT_API_PARAMETER_UPDATED, a2CoreSelUpdated , NULL);

does not seem to be getting clipboard updates, thus preventing the X
selection forwarding from working. That was why I initially couldn't
reproduce the issue of Jean-Philippe (who doesn't use -N yet, but
should, actually).

Perhaps the clipboard reporting should be given its own case in
ReportIdentifier?

Samuel