add dev scafold and day 1 solution

lib/dune

@@ -0,0 +1,2 @@
+(library
+ (name utils))

lib/utils.ml

@@ -0,0 +1,11 @@
+let read_file name =
+    let ic = open_in name in
+    let try_read () =
+        try Some (input_line ic)
+        with End_of_file -> None in
+    let rec aux acc =
+        match try_read () with
+        | Some s -> aux (s::acc)
+        | None -> close_in ic; acc in
+    aux []
+