fix typo.

Author: rouilj

share/man/man1/roundup-demo.1

@@ -74,7 +74,7 @@ This command creates a fresh demo tracker for you to experiment
 with. The email features of Roundup will be turned off (so the nosy
 feature won't send email). It does this by removing the
 \fBnosyreaction.py\fP module from the demo tracker's \fIdetectors\fP
-directory. If you wish to send email to promote the trcker to
+directory. If you wish to send email to promote the tracker to
 production, you will need to copy \fBnosyreaction.py\fP from the
 default tracker templates directory.  The \fBtemplates\fP command from
 roundup-admin(1) can help you locate a replacement.