editors.xcode: adding "open in XCode" support.

basis/editors/xcode/authors.txt

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+John Benediktsson

basis/editors/xcode/summary.txt

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+Xcode editor integration

basis/editors/xcode/xcode.factor

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+USING: definitions io.launcher kernel math math.parser parser
+namespaces prettyprint editors make ;
+IN: editors.xcode
+
+SINGLETON: xcode
+xcode editor-class set-global
+
+M: xcode editor-command ( file line -- command )
+    drop
+    [ "open" , "-a" , "XCode" , , ] { } make ;