Update PrimsJS to 1.22.0 (#16)

* Update PrimsJS to 1.22.0

* Update travis services

* Add clipboard to dependencies

Author: cherifGsoul

.travis.yml

@@ -1,5 +1,5 @@
 language: node_js
 node_js: node
-before_install:
-  - "export DISPLAY=:99.0"
-  - "sh -e /etc/init.d/xvfb start"
+dist: xenial
+services:
+  - xvfb

package.json

@@ -28,7 +28,8 @@
   "homepage": "https://github.com/bit-docs/bit-docs-html-highlight-line#readme",
   "dependencies": {
     "bit-docs-prettify": "<2.0.0",
-    "prismjs": "^1.11.0"
+    "clipboard": "^2.0.6",
+    "prismjs": "^1.22.0"
   },
   "devDependencies": {
     "bit-docs-generate-html": "^0.15.0",