Added selection sort algorithm in javascript (#33)

sorting/js/selection-sort.js

@@ -0,0 +1,15 @@
+let sort = [12,6,3,88,1,4,8]
+
+for(let i=0; i<sort.length; i++){
+    for(let j=0; j<sort.length; j++){
+        // comparing array elements
+        if(sort[j]>sort[i]){
+            //swaping elements
+            let temp = sort[i];
+            sort[i]=sort[j];
+            sort[j]= temp;
+        }
+    }
+}
+
+console.log(sort)