Update ws module

Deals with vulnerability https://nodesecurity.io/advisories/550

package.json

@@ -62,7 +62,7 @@
     "simple-statistics": "5.1.0",
     "superagent": "3.0.0",
     "winston": "2.3.0",
-    "ws": "1.1.1"
+    "ws": "3.3.1"
   },
   "devDependencies": {
     "expect.js": "0.3.1",

yarn.lock

@@ -227,6 +227,10 @@ assertion-error@^1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/assertion-error/-/assertion-error-1.0.2.tgz#13ca515d86206da0bac66e834dd397d87581094c"
 
+async-limiter@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/async-limiter/-/async-limiter-1.0.0.tgz#78faed8c3d074ab81f22b4e985d79e8738f720f8"
+
 async@^1.4.0:
   version "1.5.0"
   resolved "https://registry.yarnpkg.com/async/-/async-1.5.0.tgz#2796642723573859565633fc6274444bee2f8ce3"
@@ -1919,10 +1923,6 @@ optimist@^0.6.1:
     minimist "~0.0.1"
     wordwrap "~0.0.2"
 
-options@>=0.0.5:
-  version "0.0.6"
-  resolved "https://registry.yarnpkg.com/options/-/options-0.0.6.tgz#ec22d312806bb53e731773e7cdaefcf1c643128f"
-
 os-homedir@^1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/os-homedir/-/os-homedir-1.0.2.tgz#ffbc4988336e0e833de0c168c7ef152121aa7fb3"
@@ -2752,10 +2752,6 @@ uglify-to-browserify@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"
 
-[email protected]:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/ultron/-/ultron-1.0.2.tgz#ace116ab557cd197386a4e88f4685378c8b2e4fa"
-
 ultron@~1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/ultron/-/ultron-1.1.0.tgz#b07a2e6a541a815fc6a34ccd4533baec307ca864"
@@ -2873,20 +2869,21 @@ write-file-atomic@^1.1.4:
     imurmurhash "^0.1.4"
     slide "^1.1.5"
 
-[email protected]:
-  version "1.1.1"
-  resolved "https://registry.yarnpkg.com/ws/-/ws-1.1.1.tgz#082ddb6c641e85d4bb451f03d52f06eabdb1f018"
-  dependencies:
-    options ">=0.0.5"
-    ultron "1.0.x"
-
 [email protected]:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/ws/-/ws-3.0.0.tgz#98ddb00056c8390cb751e7788788497f99103b6c"
   dependencies:
     safe-buffer "~5.0.1"
     ultron "~1.1.0"
 
+[email protected]:
+  version "3.3.1"
+  resolved "https://registry.yarnpkg.com/ws/-/ws-3.3.1.tgz#d97e34dee06a1190c61ac1e95f43cb60b78cf939"
+  dependencies:
+    async-limiter "~1.0.0"
+    safe-buffer "~5.1.0"
+    ultron "~1.1.0"
+
 xtend@^4.0.0, xtend@~4.0.0:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/xtend/-/xtend-4.0.1.tgz#a5c6d532be656e23db820efb943a1f04998d63af"