[UI] Diff tools.

[Gary Chambers]

>One thing I noticed is that in the text panes, for selected code the
>keyboard shortcuts do not work and the usual context menu is missing.

This will be addressed in the future when tackling MC merges to allow
piecemeal conflict resolution *within* a method (pick which changes from
either side and allow modification of the composite result).

>
>Cheers,
>Adrian
>
>BTW: I still have a problem loading or updating to versions beyond
>Pinesoft-Widgets-gvc.301.mcz (even if there are no windows opened when
>loading, which we do using MC config maps). I get an emergency
>debugger from which the image cannot recover.

Unfortunately MC 1.0 having non-atomic loading and a progress bar tends to
interfere...

A workaround is to temporarily modify MCPackageLoader>>basic load to this:

basicLoad
	errorDefinitions := OrderedCollection new.
	[[additions do: [:ea | self tryToLoad: ea].
	removals do: [:ea | ea unload] displayingProgress: 'Cleaning up...'.
	self shouldWarnAboutErrors ifTrue: [self warnAboutErrors].
	errorDefinitions do: [:ea | ea loadOver: (self obsoletionFor: ea)]
displayingProgress: 'Reloading...'.
	additions do: [:ea | ea postloadOver: (self obsoletionFor: ea)]
displayingProgress: 'Initializing...']
		on: InMidstOfFileinNotification
		do: [:n | n resume: true]]
			ensure: [self flushChangesFile]


Then revert the version after Widgets is loaded.

Thanks, Gary.