deps - remove unused missippi dep

mock-dev.js

@@ -15,7 +15,6 @@
 const extend = require('xtend')
 const render = require('react-dom').render
 const h = require('react-hyperscript')
-const pipe = require('mississippi').pipe
 const Root = require('./ui/app/root')
 const configureStore = require('./ui/app/store')
 const actions = require('./ui/app/actions')

package.json

@@ -125,7 +125,6 @@
     "loglevel": "^1.4.1",
     "metamascara": "^2.0.0",
     "metamask-logo": "^2.1.2",
-    "mississippi": "^1.2.0",
     "mkdirp": "^0.5.1",
     "multiplex": "^6.7.0",
     "number-to-bn": "^1.7.0",