Add i18 support

package.json

@@ -10,6 +10,7 @@
     "build": "vue-cli-service build",
     "lint": "vue-cli-service lint",
     "cors-proxy": "node scripts/corsProxy.js",
+    "i18n:report": "vue-cli-service i18n:report --src './src/**/*.?(js|vue)' --locales './src/locales/**/*.json'",
     "test": "vue-cli-service test:unit"
   },
   "dependencies": {
@@ -20,6 +21,7 @@
     "leaflet.heat": "^0.2.0",
     "vue": "^2.6.6",
     "vue-feather-icons": "^5.0.0",
+    "vue-i18n": "^8.0.0",
     "vue-js-modal": "^1.3.31",
     "vue-outside-events": "^1.1.3",
     "vue-router": "^3.1.3",
@@ -45,6 +47,7 @@
     "lint-staged": "^9.5.0",
     "node-sass": "^4.13.0",
     "sass-loader": "^8.0.0",
+    "vue-cli-plugin-i18n": "^0.6.0",
     "vue-template-compiler": "^2.5.21"
   },
   "license": "MIT",