diff --git a/package-lock.json b/package-lock.json
index 9d42ede..d5c0d6b 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1959,7 +1959,8 @@
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       "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.2.tgz",
-      "integrity": "sha1-tf1UIgqivFq1eqtxQMlAdUUDwac="
+      "integrity": "sha1-tf1UIgqivFq1eqtxQMlAdUUDwac=",
+      "dev": true
     },
     "cross-spawn": {
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@@ -3272,7 +3273,8 @@
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       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
-      "integrity": "sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE="
+      "integrity": "sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE=",
+      "dev": true
     },
     "isexe": {
       "version": "2.0.0",
@@ -5712,7 +5714,8 @@
     "process-nextick-args": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/process-nextick-args/-/process-nextick-args-2.0.0.tgz",
-      "integrity": "sha512-MtEC1TqN0EU5nephaJ4rAtThHtC86dNN9qCuEhtshvpVBkAW5ZO7BASN9REnF9eoXGcRub+pFuKEpOHE+HbEMw=="
+      "integrity": "sha512-MtEC1TqN0EU5nephaJ4rAtThHtC86dNN9qCuEhtshvpVBkAW5ZO7BASN9REnF9eoXGcRub+pFuKEpOHE+HbEMw==",
+      "dev": true
     },
     "progress": {
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@@ -6035,7 +6038,8 @@
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       "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.1.tgz",
-      "integrity": "sha512-kKvNJn6Mm93gAczWVJg7wH+wGYWNrDHdWvpUmHyEsgCtIwwo3bqPtV4tR5tuPaUhTOo/kvhVwd8XwwOllGYkbg=="
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+      "dev": true
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     "safe-regex": {
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@@ -6776,34 +6780,34 @@
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-      "version": "2.0.5",
-      "resolved": "https://registry.npmjs.org/through2/-/through2-2.0.5.tgz",
-      "integrity": "sha512-/mrRod8xqpA+IHSLyGCQ2s8SPHiCDEeQJSep1jqLYeEUClOFG2Qsh+4FU6G9VeqpZnGW/Su8LQGc4YKni5rYSQ==",
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/through2/-/through2-4.0.2.tgz",
+      "integrity": "sha512-iOqSav00cVxEEICeD7TjLB1sueEL+81Wpzp2bY17uZjZN0pWZPuo4suZ/61VujxmqSGFfgOcNuTZ85QJwNZQpw==",
       "requires": {
-        "readable-stream": "~2.3.6",
-        "xtend": "~4.0.1"
+        "readable-stream": "3"
       },
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-          "version": "2.3.7",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
-          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "version": "3.6.0",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-3.6.0.tgz",
+          "integrity": "sha512-BViHy7LKeTz4oNnkcLJ+lVSL6vpiFeX6/d3oSH8zCW7UxP2onchk+vTGB143xuFjHS3deTgkKoXXymXqymiIdA==",
           "requires": {
-            "core-util-is": "~1.0.0",
-            "inherits": "~2.0.3",
-            "isarray": "~1.0.0",
-            "process-nextick-args": "~2.0.0",
-            "safe-buffer": "~5.1.1",
-            "string_decoder": "~1.1.1",
-            "util-deprecate": "~1.0.1"
+            "inherits": "^2.0.3",
+            "string_decoder": "^1.1.1",
+            "util-deprecate": "^1.0.1"
           }
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+        "safe-buffer": {
+          "version": "5.2.1",
+          "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.2.1.tgz",
+          "integrity": "sha512-rp3So07KcdmmKbGvgaNxQSJr7bGVSVk5S9Eq1F+ppbRo70+YeaDxkw5Dd8NPN+GD6bjnYm2VuPuCXmpuYvmCXQ=="
+        },
         "string_decoder": {
-          "version": "1.1.1",
-          "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
-          "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
+          "version": "1.3.0",
+          "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.3.0.tgz",
+          "integrity": "sha512-hkRX8U1WjJFd8LsDJ2yQ/wWWxaopEsABU1XfkM8A+j0+85JAGppt16cr1Whg6KIbb4okU6Mql6BOj+uup/wKeA==",
           "requires": {
-            "safe-buffer": "~5.1.0"
+            "safe-buffer": "~5.2.0"
           }
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@@ -7288,11 +7292,6 @@
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       "dev": true
     },
-    "xtend": {
-      "version": "4.0.2",
-      "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
-      "integrity": "sha512-LKYU1iAXJXUgAXn9URjiu+MWhyUXHsvfp7mcuYm9dSUKK0/CjtrUwFAxD82/mCWbtLsGjFIad0wIsod4zrTAEQ=="
-    },
     "y18n": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/y18n/-/y18n-4.0.0.tgz",
diff --git a/package.json b/package.json
index 3d7ef8f..bf87e03 100644
--- a/package.json
+++ b/package.json
@@ -30,7 +30,7 @@
     "commander": "^2.20.3",
     "log4js": "^6.1.1",
     "pkginfo": "^0.4.1",
-    "through2": "^2.0.5",
+    "through2": "^4.0.2",
     "url-parse-lax": "^3.0.0"
   },
   "devDependencies": {