fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-LODASH-450202

package.json

@@ -6,23 +6,23 @@
     "main": "lib/index.js",
     "dependencies": {
         "q": "1.0.1",
-        "lodash": "3.10.1",
+        "lodash": "4.17.12",
         "graceful-fs": "3.0.5",
         "resolve": "0.6.3",
         "fs-extra": "0.16.5",
         "fstream-ignore": "1.0.2",
         "gitbook-parsers": "0.8.9",
         "gitbook-plugin-highlight": "1.0.3",
         "gitbook-plugin-sharing": "1.0.1",
-        "gitbook-plugin-search": "1.1.0",
+        "gitbook-plugin-search": "2.0.0",
         "gitbook-plugin-fontsettings": "1.0.2",
         "nunjucks": "2.2.0",
         "nunjucks-autoescape": "1.0.0",
         "nunjucks-filter": "1.0.0",
         "i18n": "0.5.0",
         "semver": "5.0.1",
         "npmi": "0.1.1",
-        "cheerio": "0.19.0",
+        "cheerio": "0.20.0",
         "gitbook-plugin-livereload": "0.0.1",
         "chokidar": "~1.0.5",
         "send": "0.2.0",
@@ -36,10 +36,10 @@
         "dom-serializer": "0.1.0",
         "spawn-cmd": "0.0.2",
         "escape-string-regexp": "1.0.3",
-        "juice": "1.5.0",
+        "juice": "2.0.0",
         "jsonschema": "1.0.2",
         "json-schema-defaults": "0.1.1",
-        "merge-defaults": "0.2.1",
+        "merge-defaults": "0.2.2",
         "github-slugid": "1.0.0"
     },
     "devDependencies": {