Fix typos.

src/Editor.cpp

@@ -1268,7 +1268,7 @@ void Editor::EnsureCaretVisible(bool useMargin, bool vert, bool horiz) {
 					yMarginT = yMarginB = 0;
 				} else {
 					// yMarginT must equal to caretYSlop, with a minimum of 1 and
-					// a maximum of slightly less than half the heigth of the text area.
+					// a maximum of slightly less than half the height of the text area.
 					yMarginT = Platform::Clamp(caretYSlop, 1, halfScreen);
 					if (bEven) {
 						yMarginB = yMarginT;