Adds 2018, Day 17 to main ToC

Author: romellem

README.md

@@ -79,7 +79,7 @@ Completed: **14 / 25** (56%)
 
 ## 2018 Puzzles List
 
-Completed: **20 / 25** (80%)
+Completed: **21 / 25** (84%)
 
 *  [✅ Day 1](2018/1/)
 *  [✅ Day 2](2018/2/)
@@ -97,7 +97,7 @@ Completed: **20 / 25** (80%)
 *  [✅ Day 14](2018/14/)
 *  Day 15
 *  [✅ Day 16](2018/16/)
-*  Day 17
+*  [✅ Day 17](2018/17/)
 *  [✅ Day 18](2018/18/)
 *  [✅ Day 19](2018/19/)
 *  Day 20