diff --git a/package-lock.json b/package-lock.json
index d018938..3c1aef8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -151,7 +151,7 @@
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-          "resolved": "http://registry.npmjs.org/util/-/util-0.10.3.tgz",
+          "resolved": "https://registry.npmjs.org/util/-/util-0.10.3.tgz",
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@@ -454,7 +454,7 @@
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-              "resolved": "http://registry.npmjs.org/through2/-/through2-1.1.1.tgz",
+              "resolved": "https://registry.npmjs.org/through2/-/through2-1.1.1.tgz",
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@@ -493,7 +493,7 @@
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-          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-1.1.14.tgz",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-1.1.14.tgz",
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@@ -505,7 +505,7 @@
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-          "resolved": "http://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
+          "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
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@@ -639,7 +639,7 @@
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-          "resolved": "http://registry.npmjs.org/commander/-/commander-2.8.1.tgz",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-2.8.1.tgz",
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@@ -648,7 +648,7 @@
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-          "resolved": "http://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
+          "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
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@@ -756,7 +756,7 @@
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-          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.0.6.tgz",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.0.6.tgz",
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@@ -1078,18 +1078,32 @@
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-      "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.4.1.tgz",
-      "integrity": "sha512-BsXLz5sqX8OHcsh7CqBMztyXARmGQ3LWPtGjJi6DiJHq5C/qvi9P3OqgswKSDftbu8+IoI/QDTAm2fFnQ9SZSQ==",
+      "version": "6.5.4",
+      "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.4.tgz",
+      "integrity": "sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==",
       "dev": true,
       "requires": {
-        "bn.js": "^4.4.0",
-        "brorand": "^1.0.1",
+        "bn.js": "^4.11.9",
+        "brorand": "^1.1.0",
         "hash.js": "^1.0.0",
-        "hmac-drbg": "^1.0.0",
-        "inherits": "^2.0.1",
-        "minimalistic-assert": "^1.0.0",
-        "minimalistic-crypto-utils": "^1.0.0"
+        "hmac-drbg": "^1.0.1",
+        "inherits": "^2.0.4",
+        "minimalistic-assert": "^1.0.1",
+        "minimalistic-crypto-utils": "^1.0.1"
+      },
+      "dependencies": {
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+          "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.12.0.tgz",
+          "integrity": "sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==",
+          "dev": true
+        },
+        "inherits": {
+          "version": "2.0.4",
+          "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+          "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
+          "dev": true
+        }
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@@ -1318,7 +1332,7 @@
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-          "resolved": "http://registry.npmjs.org/commander/-/commander-2.9.0.tgz",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-2.9.0.tgz",
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@@ -2304,7 +2318,7 @@
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-      "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",
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       "dev": true,
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