Add rudimentary JavaScript highlighting to query text view

MongoView/Synax Highlighting/JavaScriptHighlighter.swift

@@ -231,12 +231,9 @@ class JavaScriptHighlighter {
     }
     
     private func consumeObjectKey() {
-        guard let char = peek() else { return }
         let keyStart = currentIndex!
-        if identifierStarts.contains(char) {
-            consumeIdentifier()
-        } else if char == "'" || char == "\"" {
-            consumeString()
+        while let char = peek(), identifiers.contains(char) {
+            consume()
         }
         print("Object key: '\(text[keyStart..<currentIndex])'")
     }