add dev scafold and day 1 solution

bin/d1/dune

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+(executable
+ (public_name d1)
+ (name main)
+ (libraries core utils))

bin/d1/main.ml

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+let sum_callories input =
+    let rec aux elv res = function
+        | [] -> elv :: res
+        | x :: xs -> if x = "" then aux 0 (elv :: res) xs
+                     else aux (elv + (int_of_string x)) res xs in
+    aux 0 [] input
+
+open Utils
+
+let summed = read_file "bin/d1/input.txt"
+            |> sum_callories
+            |> List.sort compare
+            |> List.rev ;;
+
+open Core
+
+let first = List.hd summed |> Option.value ~default:0 ;;
+let second = List.take summed 3 |> List.fold ~init:0 ~f:(+) ;;
+
+"\n1: " ^ (string_of_int first) ^
+"\n2: " ^ (string_of_int second) |> print_endline

bin/dune

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+(executable
+ (public_name aoc2022)
+ (name main))

bin/main.ml

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+print_endline "\n" ;;
+print_endline "Nothing here. You can run an executable for a single day with:" ;;
+print_endline "dune exec d1" ;;