Fix various linter errors

src/test/datalayout-test.js

@@ -4,7 +4,6 @@ import DataLayout from '../datalayout.js';
 import expect from 'expect.js';
 
 /* global describe:false */
-/* global before:false */
 
 describe('DataLayout', function () {
     describe('no dirMap', function () {

src/test/syncer-test.js

@@ -280,7 +280,8 @@ describe('Syncer', function () {
         });
 
         const dataLayout = new DataLayout(gTmpDir, []);
-        let changes = await getChanges(dataLayout);
+        let changes;
+        await getChanges(dataLayout);
 
         execSync(`rm a; \
                     mkdir a; \

src/test/underscore-test.js

@@ -1,4 +1,4 @@
-/* global it, describe, before, after */
+/* global it, describe */
 
 import expect from 'expect.js';
 import _ from '../underscore.js';

src/test/validator-test.js

@@ -1,4 +1,4 @@
-/* global it, describe, before, after */
+/* global it, describe */
 
 import expect from 'expect.js';
 import validator from '../validator.js';