Adds 2019, Day 16 to main ToC

Author: romellem

README.md

@@ -49,7 +49,7 @@ Completed: **25 / 25** (100% ⭐️)
 
 ## 2019 Puzzles List
 
-Completed: **16 / 25** (64%)
+Completed: **17 / 25** (68%)
 
 *  [✅ Day 1](2019/1/)
 *  [✅ Day 2](2019/2/)
@@ -66,7 +66,7 @@ Completed: **16 / 25** (64%)
 *  [✅ Day 13](2019/13/)
 *  [✅ Day 14](2019/14/)
 *  Day 15
-*  Day 16
+*  [✅ Day 16](2019/16/)
 *  Day 17
 *  Day 18
 *  [✅ Day 19](2019/19/)