extracted streams, date-format into separate modules

lib/appenders/dateFile.js

@@ -1,5 +1,5 @@
 "use strict";
-var streams = require('../streams')
+var streams = require('streamroller')
 , layouts = require('../layouts')
 , path = require('path')
 , os = require('os')

lib/appenders/file.js

@@ -2,7 +2,7 @@
 var layouts = require('../layouts')
 , path = require('path')
 , fs = require('fs')
-, streams = require('../streams')
+, streams = require('streamroller')
 , os = require('os')
 , eol = os.EOL || '\n'
 , openFiles = [];