Updated equals doc

pkg/yqlib/doc/operators/headers/equals.md

@@ -1,4 +1,4 @@
-# Equals
+# Equals / Not Equals
 
 This is a boolean operator that will return `true` if the LHS is equal to the RHS and `false` otherwise.
 
@@ -11,3 +11,5 @@ It is most often used with the select operator to find particular nodes:
 ```
 select(.a == .b)
 ```
+
+The not equals `!=` operator returns `false` if the LHS is equal to the RHS.