update dependencies (#1009)

* update deps

* remove node v4 from travis

.travis.yml

@@ -1,7 +1,6 @@
 language: node_js
 
 node_js:
-  - '4'
   - '6'
   - '8'
   - 'node'

package.json

@@ -42,7 +42,7 @@
     "dat-doctor": "^1.2.5",
     "dat-encoding": "^5.0.1",
     "dat-json": "^1.0.0",
-    "dat-link-resolve": "^2.1.0",
+    "dat-link-resolve": "^2.2.0",
     "dat-log": "^1.1.0",
     "dat-node": "^3.5.5",
     "dat-registry": "^4.0.0",
@@ -51,7 +51,7 @@
     "prettier-bytes": "^1.0.3",
     "progress-string": "^1.2.1",
     "prompt": "^1.0.0",
-    "pump": "^2.0.0",
+    "pump": "^3.0.0",
     "rimraf": "^2.6.1",
     "speedometer": "^1.0.0",
     "subcommand": "^2.1.0",
@@ -62,11 +62,11 @@
   "devDependencies": {
     "cross-zip-cli": "^1.0.0",
     "dependency-check": "^3.0.0",
-    "hypercore": "^6.12.0",
-    "hyperdiscovery": "^7.0.0",
+    "hypercore": "^6.17.2",
+    "hyperdiscovery": "^8.0.0",
     "mkdirp": "^0.5.1",
-    "pkg": "^4.2.6",
-    "random-access-memory": "^2.4.0",
+    "pkg": "^4.3.3",
+    "random-access-memory": "^3.0.0",
     "recursive-readdir-sync": "^1.0.6",
     "request": "^2.81.0",
     "standard": "^11.0.1",