update various deps.

Author: ctalkington

package-lock.json

@@ -29,13 +29,13 @@
     "buffer-crc32": "^0.2.13",
     "crc32-stream": "^3.0.1",
     "normalize-path": "^3.0.0",
-    "readable-stream": "^2.3.6"
+    "readable-stream": "^2.3.7"
   },
   "devDependencies": {
     "chai": "^4.0.0",
+    "mkdirp": "^0.5.5",
     "mocha": "^5.0.0",
-    "rimraf": "^2.4.3",
-    "mkdirp": "^0.5.0"
+    "rimraf": "^2.7.1"
   },
   "keywords": [
     "compress",