Updated XS externals to 4.2.4
v1.6.6
[Editing] Abort references highlighting after 3 seconds.
Merge pull request #437 from Orvid/master

[Completion/GUI] Refactored the icon dictionary's initialization
[Editing/Gui] Refactored Node-specific Icon-getting; Exported the class into a separate file
nre
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v1.6.7
v1.6.8
Added icons for the various instruction sets.