add npm 5.6.0 to package.json

debian/patches/0420-use-system-libs.patch

@@ -1,8 +1,10 @@
 --- a/package.json
 +++ b/package.json
-@@ -13,16 +13,8 @@
+@@ -12,17 +12,10 @@
+     "webpack-prod": "NODE_ENV=production webpack --config config/webpack.config.js"
    },
    "dependencies": {
++    "npm": "5.6.0",
      "axios": "^0.16.2",
 -    "babel-core": "^6.22.1",
 -    "babel-eslint": "^7.2.1",
@@ -17,7 +19,7 @@
      "cropper": "^2.3.0",
      "css-loader": "^0.28.0",
      "d3": "^3.5.11",
-@@ -30,25 +22,14 @@
+@@ -30,25 +23,14 @@
      "document-register-element": "^1.3.0",
      "dropzone": "^4.2.0",
      "emoji-unicode-version": "^0.2.1",
@@ -43,7 +45,7 @@
      "react-dev-utils": "^0.5.2",
      "select2": "3.5.2-browserify",
      "sql.js": "^0.4.0",
-@@ -56,14 +37,11 @@
+@@ -56,14 +38,11 @@
      "three-orbit-controls": "^82.1.0",
      "three-stl-loader": "^1.0.4",
      "timeago.js": "^2.0.5",