added selectGroupedControls of group and pre-parsing filename
Leaving filename on pre-process list so there is a known precedence on setting text and filename. Changed pre-process to be case insensitive (docs!!). Changed setfilename to handle setting the filename to empty when there is imported image data.
Made image text work the same way as filename. If the filename or text is empty then setting them to empty does not set the image rep to nil.
handle short name… ensure empty if not set rather than abbrev id
Merge branch 'bugfix/iss8884' of https://github.com/montegoulding/livecode into feature-revised_properties_prop
[[ RevisedPropsProp ]] Reverted behavior changes to image text/filename setters temporarily - to reinstate for next release (Bug 10977)
[[ RevisedPropsProp ]] Added work-around to bug 10977 - make sure image/filename of an image are only set if the value is non-empty when setting 'the properties'.
[[ RevisedPropsProp ]] Fixed preprocess check for whether to set a property (previously had no effect as 'continue' acted on the inner 'for' statement).