Implement most of the spec reusing scribe & nefthera code

ocaml/test/test_tori.ml

@@ -0,0 +1,15 @@
+module Reader = Tori.System.Process.Reader
+module File = Tori.System.File
+
+let smoke () =
+
+    (* Executing echo should return the same string on output *)
+    let result = Reader.read [||] "echo 0x70121" in
+    assert (Reader.format result = "0x70121");
+
+    (* Reading a file, relying on Dune's directory structure *)
+    let file_contents = File.read "../tori.opam" in
+    let contents_list = String.split_on_char '\n' file_contents in
+    assert (List.mem "depends: [" contents_list)
+
+let () = smoke ()