remove problematic unused dep

package.json

@@ -56,7 +56,6 @@
     "jsdom": "9.6.0",
     "jsdom-global": "2.1.0",
     "matcha": "^0.7.0",
-    "microtime": "2.1.1",
     "mocha": "^2.5.3",
     "np": "^2.9.0",
     "npm-run-all": "^2.3.0",

yarn.lock

@@ -1057,10 +1057,6 @@ binary-extensions@^1.0.0:
   version "1.8.0"
   resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-1.8.0.tgz#48ec8d16df4377eae5fa5884682480af4d95c774"
 
-bindings@1.2.x:
-  version "1.2.1"
-  resolved "https://registry.yarnpkg.com/bindings/-/bindings-1.2.1.tgz#14ad6113812d2d37d72e67b4cacb4bb726505f11"
-
 bl@^0.7.0:
   version "0.7.0"
   resolved "https://registry.yarnpkg.com/bl/-/bl-0.7.0.tgz#3fb0670602ac2878eb770dc2039f1836be62ae5b"
@@ -4146,13 +4142,6 @@ micromatch@^2.1.5, micromatch@^2.3.11:
     parse-glob "^3.0.4"
     regex-cache "^0.4.2"
 
-microtime@2.1.1:
-  version "2.1.1"
-  resolved "https://registry.yarnpkg.com/microtime/-/microtime-2.1.1.tgz#654294b560e32fc97c4bf4b8156d5f2e4d5fd183"
-  dependencies:
-    bindings "1.2.x"
-    nan "2.3.x"
-
 miller-rabin@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/miller-rabin/-/miller-rabin-4.0.0.tgz#4a62fb1d42933c05583982f4c716f6fb9e6c6d3d"
@@ -4299,7 +4288,7 @@ mz@^2.3.1:
     object-assign "^4.0.1"
     thenify-all "^1.0.0"
 
-nan@2.3.x, nan@^2.3.0:
+nan@^2.3.0:
   version "2.3.5"
   resolved "https://registry.yarnpkg.com/nan/-/nan-2.3.5.tgz#822a0dc266290ce4cd3a12282ca3e7e364668a08"