Add day 2

Day 2 was a breeze, and part 2 followed on very nicely from part 1.

I expected part 2 to be something similar to the elf not adding cubes
back into the bag, but I was able to adapt my solution just fine anyway.

Nothing much to say beyond that, but I always expect early AOC to be
easy enough - I'm sure I'll be porting my Python pathfinding library to
Rust soon enough ;)

Change-Id: Ic9daab4439b68885375cb5fcb9c6728db6ef4f47
Reviewed-on: https://git.clicks.codes/c/Minion/AdventOfCode/2023/+/99
diff --git a/.gitignore b/.gitignore
index 5f518d3..64a7457 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 *.log
 tmp/
 input.txt
+target/