Merge pull request #231 from feross/greenkeeper/airtap-2.0.2

chore(package): update airtap to version 2.0.2

diff --cc package.json
index df98372d6a24ad91d243c9a8e702bb4751745f42,85a04979b41d0e978faebf99a30e44f6ecfc13af..f9f3ba74a133f0047d7cae65dc105b918125bd72
--- 1/package.json
--- 2/package.json
+++ b/package.json
@@@ -19,10 -19,10 +19,10 @@@
      "ieee754": "^1.1.4"
    },
    "devDependencies": {
-     "airtap": "0.1.0",
+     "airtap": "2.0.2",
      "benchmark": "^2.0.0",
      "browserify": "^16.1.0",
 -    "concat-stream": "^1.4.7",
 +    "concat-stream": "^2.0.0",
      "hyperquest": "^2.0.0",
      "is-buffer": "^2.0.0",
      "is-nan": "^1.0.1",