DEV 559: Refactor CLI and add customizations (#57)

* move snake API structs into a new client package

* add customizations to snake objects

* refactor and add support for passing snake customizations in games

test_utils.go

@@ -1,35 +0,0 @@
-package rules
-
-import (
-	"bytes"
-	"encoding/json"
-	"flag"
-	"io/ioutil"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-var updateFixtures = flag.Bool("update-fixtures", false, "Regenerate fixtures in testdata based on current test output")
-
-// RequireJSONMatchesFixture asserts that the JSON text in actual matches the
-// JSON read from filename, without taking into account whitespace and
-// ordering. Files can be specified relative to the calling test (e.g.
-// testdata/example.json). To regenerate the expected test data automatically
-// after making a code change, pass the `-update-fixtures` flag to `go test`.
-func RequireJSONMatchesFixture(t *testing.T, filename string, actual string) {
-	t.Helper()
-
-	if *updateFixtures {
-		var indented bytes.Buffer
-		err := json.Indent(&indented, []byte(actual), "", "  ")
-		require.NoError(t, err, "Failed to indent JSON")
-		err = ioutil.WriteFile(filename, indented.Bytes(), 0644)
-		require.NoError(t, err, "Failed to update fixture", filename)
-	}
-
-	expectedData, err := ioutil.ReadFile(filename)
-	require.NoError(t, err, "Failed to read fixture", filename)
-
-	require.JSONEq(t, string(expectedData), actual)
-}