Implement hashStream

Add a hashStream method to lib/hash that does the same as hashFile only
with a stream instead of a file path and implement tests for both of
these methods.

test/file/hash.txt

@@ -0,0 +1 @@
+The quick brown fox jumps over the lazy dog

test/lib/hash.js

@@ -0,0 +1,24 @@
+const assert = require('assert').strict;
+const fs = require('fs');
+const path = require('path');
+const stream = require('stream');
+
+const hash = require('lib/hash');
+
+
+describe("lib/hash", function() {
+	describe("hashStream()", function() {
+		it("should hash a stream of bytes", async function() {
+			let stream = fs.createReadStream(path.join("test", "file", "hash.txt"));
+			let result = await hash.hashStream(stream);
+			assert.equal(result, "be417768b5c3c5c1d9bcb2e7c119196dd76b5570");
+		});
+	});
+
+	describe("hashFile()", function() {
+		it("should hash a file", async function() {
+			let result = await hash.hashFile(path.join("test", "file", "hash.txt"));
+			assert.equal(result, "be417768b5c3c5c1d9bcb2e7c119196dd76b5570");
+		});
+	});
+});

test/missing.js

@@ -4,7 +4,6 @@
 require('lib/clusterTools');
 require('lib/dole_nn_base');
 require('lib/getInstances');
-require('lib/hash');
 require('lib/manager/instanceManager');
 require('lib/manager/modManager');
 require('lib/manager/pluginManager');