Closes #2754

Bumping them for every release just adds too much git
noise and history blowup.

Issue #2529

Issue #2438

Issue #2438

Issue #2334

And listen for them in the merge addon.

(otherwise there is an error if all is minified in one file)

Previous behaviour was to only update the displayed differences if
the edit pane was modified.  There exists use-cases such that the
differences should be updated when any of the panes change.

I don't expect this to introduce any performance regressions due
to the existing debounce code within the update function.

Signed-off-by: ciaranj <ciaranj@gmail.com>

Issue #1765

Provides new option (highlightDifferences) and method highlightDifferences(bool)
to the MergeView plugin.

If true (or undefined) the original behaviour is maintained, which is to show
the differences (line highlighting and gutter graphics), if false then
the changes will not be shown.

Calling the method causes the visual change to occur 'immediately'

Signed-off-by: ciaranj <ciaranj@gmail.com>

Since the addon is called merge, not diff.

Apparenly Firefox still hasn't caught up on the unprefixed version.

Work around percentage width rounding problems.