Refer to previous version by number

Replace the text "the previous version" with "DALI 1.1" so that this
text does not need to be updated in future document versions.

DALI.tex

@@ -748,7 +748,7 @@ \subsection{Point}
 \end{verbatim}
 
 Coordinate values are not limited to fall within a defined valid range; this is a change from
-the previous version where equatorial coordinates were explicitly limited. Software may have
+DALI 1.1 where equatorial coordinates were explicitly limited. Software may have
 to perform range reduction in some coordinate systems (for example, spherical coordinates) in 
 order to correctly interpret or use the coordinate values. Coordinate values are more likely to
 work as expected if they are expressed in the simplest form and do not require range reduction.