docs: update README

Author: marcelblijleven

README.md

@@ -23,7 +23,7 @@ Collection of my Advent of Code solutions in an overkill project setup 👻🎄.
 <!-- start completed section -->
 ## Completed ⭐️
 ### 2015
-<details><summary>Solutions overview of 2015</summary>
+<details><summary>Solutions for 2015</summary>
 <p>
 
 | day   | part one | part two |
@@ -58,7 +58,7 @@ Collection of my Advent of Code solutions in an overkill project setup 👻🎄.
 </details>
 
 ### 2020
-<details><summary>Solutions overview of 2020</summary>
+<details><summary>Solutions for 2020</summary>
 <p>
 
 | day   | part one | part two |
@@ -78,13 +78,12 @@ Collection of my Advent of Code solutions in an overkill project setup 👻🎄.
 | 13 | ⭐️ | ⭐️ |
 | 14 | ⭐️ | ⭐️ |
 | 15 | ⭐️ | ⭐️ |
-| 16 | ⭐️ | ⭐️ |
 
 </p>
 </details>
 
 ### 2021
-<details><summary>Solutions overview of 2021</summary>
+<details><summary>Solutions for 2021</summary>
 <p>
 
 | day   | part one | part two |

src/adventofcode/year_2020/README.md

@@ -1,5 +1,5 @@
 # 2020
-Solutions for 16 days in 2020 with a total of 32 stars collected
+Solutions for 15 days in 2020 with a total of 30 stars collected
 
 | day   | part one | part two |
 | :---: | :------: | :------: |
@@ -17,5 +17,4 @@ Solutions for 16 days in 2020 with a total of 32 stars collected
 | 12 | ⭐️ | ⭐️ |
 | 13 | ⭐️ | ⭐️ |
 | 14 | ⭐️ | ⭐️ |
-| 15 | ⭐️ | ⭐️ |
-| 16 | ⭐️ | ⭐️ |
+| 15 | ⭐️ | ⭐️ |