diff --git a/package-lock.json b/package-lock.json
index a48e98e..809b021 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -13,7 +13,8 @@
     "acorn": {
       "version": "2.7.0",
       "resolved": "https://registry.npmjs.org/acorn/-/acorn-2.7.0.tgz",
-      "integrity": "sha1-q259nYhqrKiwhbwzEreaGYQz8Oc="
+      "integrity": "sha1-q259nYhqrKiwhbwzEreaGYQz8Oc=",
+      "optional": true
     },
     "acorn-globals": {
       "version": "1.0.9",
@@ -24,14 +25,6 @@
         "acorn": "^2.1.0"
       }
     },
-    "agent-base": {
-      "version": "4.2.1",
-      "resolved": "https://registry.npmjs.org/agent-base/-/agent-base-4.2.1.tgz",
-      "integrity": "sha512-JVwXMr9nHYTUXsBFKUqhJwvlcYU/blreOEUkhNR2eXZIvwd+c+o5V4MgDPKWnMS/56awN3TRzIP+KoPn+roQtg==",
-      "requires": {
-        "es6-promisify": "^5.0.0"
-      }
-    },
     "ajv": {
       "version": "5.5.2",
       "resolved": "https://registry.npmjs.org/ajv/-/ajv-5.5.2.tgz",
@@ -197,7 +190,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "requires": {
             "core-util-is": "~1.0.0",
@@ -243,7 +236,8 @@
     "cssom": {
       "version": "0.3.2",
       "resolved": "https://registry.npmjs.org/cssom/-/cssom-0.3.2.tgz",
-      "integrity": "sha1-uANhcMefB6kP8vFuIihAJ6JDhIs="
+      "integrity": "sha1-uANhcMefB6kP8vFuIihAJ6JDhIs=",
+      "optional": true
     },
     "cssstyle": {
       "version": "0.2.37",
@@ -486,7 +480,7 @@
       "dependencies": {
         "combined-stream": {
           "version": "1.0.6",
-          "resolved": "http://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
+          "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
           "integrity": "sha1-cj599ugBrFYTETp+RFqbactjKBg=",
           "requires": {
             "delayed-stream": "~1.0.0"
@@ -587,12 +581,22 @@
       }
     },
     "https-proxy-agent": {
-      "version": "2.2.1",
-      "resolved": "https://registry.npmjs.org/https-proxy-agent/-/https-proxy-agent-2.2.1.tgz",
-      "integrity": "sha512-HPCTS1LW51bcyMYbxUIOO4HEOlQ1/1qRaFWcyxvwaqUS9TY88aoEuHUY33kuAh1YhVVaDQhLZsnPd+XNARWZlQ==",
+      "version": "2.2.4",
+      "resolved": "https://registry.npmjs.org/https-proxy-agent/-/https-proxy-agent-2.2.4.tgz",
+      "integrity": "sha512-OmvfoQ53WLjtA9HeYP9RNrWMJzzAz1JGaSFr1nijg0PVR1JaD/xbJq1mdEIIlxGpXp9eSe/O2LgU9DJmTPd0Eg==",
       "requires": {
-        "agent-base": "^4.1.0",
+        "agent-base": "^4.3.0",
         "debug": "^3.1.0"
+      },
+      "dependencies": {
+        "agent-base": {
+          "version": "4.3.0",
+          "resolved": "https://registry.npmjs.org/agent-base/-/agent-base-4.3.0.tgz",
+          "integrity": "sha512-salcGninV0nPrwpGNn4VTXBb1SOuXQBiqbrNXoeizJsHrsL6ERFM2Ne3JUSBWRE6aeNJI2ROP/WEEIDUiDe3cg==",
+          "requires": {
+            "es6-promisify": "^5.0.0"
+          }
+        }
       }
     },
     "inflight": {
@@ -871,7 +875,8 @@
     "prelude-ls": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.1.2.tgz",
-      "integrity": "sha1-IZMqVJ9eUv/ZqCf1cOBL5iqX2lQ="
+      "integrity": "sha1-IZMqVJ9eUv/ZqCf1cOBL5iqX2lQ=",
+      "optional": true
     },
     "process-nextick-args": {
       "version": "2.0.0",
@@ -1091,6 +1096,7 @@
       "version": "0.3.2",
       "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.3.2.tgz",
       "integrity": "sha1-WITKtRLPHTVeP7eE8wgEsrUg23I=",
+      "optional": true,
       "requires": {
         "prelude-ls": "~1.1.2"
       }