Implement BigInt64 and BigUint64 typedArrays (#4151)

Also implemented ToBigInt conversion method based on ECMA-262 v11, 7.1.13

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

tests/jerry/es.next/regression-test-issue-2143.js

@@ -13,4 +13,10 @@
 // limitations under the License.
 
 var a = new Uint8Array(2);
-a[0] = { valueOf : function() { throw "intoint"; } };
+
+try {
+  a[0] = { valueOf : function() { throw "intoint"; } };
+  assert(false);
+} catch (e) {
+  assert(e === "intoint")
+}