chore(npm): add front-matter package

Author: garyng

package.json

@@ -34,6 +34,7 @@
  "bash-color": "0.0.3",
  "cheerio": "^0.20.0",
  "commander": "^2.9.0",
+ "front-matter": "^2.1.1",
  "fs-extra": "^0.26.2",
  "iconv-lite": "^0.4.13",
  "lodash": "^3.10.1",