Merge pull request #2358 from thelounge/greenkeeper/yarn-1.6.0

Update yarn to the latest version 🚀

package.json

@@ -62,7 +62,7 @@
     "urijs": "1.19.1",
     "uuid": "3.2.1",
     "web-push": "3.3.0",
-    "yarn": "1.5.1"
+    "yarn": "1.6.0"
   },
   "devDependencies": {
     "@fortawesome/fontawesome-free-webfonts": "1.0.6",

yarn.lock

@@ -8531,9 +8531,9 @@ yargs@~3.10.0:
     decamelize "^1.0.0"
     window-size "0.1.0"
 
-yarn@1.5.1:
-  version "1.5.1"
-  resolved "https://registry.yarnpkg.com/yarn/-/yarn-1.5.1.tgz#e8680360e832ac89521eb80dad3a7bc27a40bab4"
+yarn@1.6.0:
+  version "1.6.0"
+  resolved "https://registry.yarnpkg.com/yarn/-/yarn-1.6.0.tgz#9cec6f7986dc237d39ec705ce74d95155fe55d4b"
 
 yeast@0.1.2:
   version "0.1.2"