Add exercise question for array methods in javascript

Author: MoisesTR

docs/Exercise/JavaScript_Basics/array_method.md

@@ -0,0 +1,4 @@
+1. **Create** an array called `numbers` 
+2. **Create** an empty array called `newArray`
+3. **Iterate** through each element in the numbers array
+4. **Alter** any element and put the altered value into the new array