moved options parsing into separate file and created test

moved the options paring system into it's own function so that it may be testable

index.js

@@ -9,44 +9,11 @@ var trigger = require("./lib/events/trigger.js")
 var Pjax = function(options) {
     this.firstrun = true
 
-    this.options = options
-    this.options.elements = this.options.elements || "a[href], form[action]"
-    this.options.selectors = this.options.selectors || ["title", ".js-Pjax"]
-    this.options.switches = this.options.switches || {}
-    this.options.switchesOptions = this.options.switchesOptions || {}
-    this.options.history = this.options.history || true
-    this.options.analytics = this.options.analytics || function(options) {
-      // options.backward or options.foward can be true or undefined
-      // by default, we do track back/foward hit
-      // https://productforums.google.com/forum/#!topic/analytics/WVwMDjLhXYk
-      if (window._gaq) {
-        _gaq.push(["_trackPageview"])
-      }
-      if (window.ga) {
-        ga("send", "pageview", {page: options.url, title: options.title})
-      }
-    }
-    this.options.scrollTo = (typeof this.options.scrollTo === 'undefined') ? 0 : this.options.scrollTo;
-    this.options.debug = this.options.debug || false
-
-    this.maxUid = this.lastUid = newUid()
-
-    // we can’t replace body.outerHTML or head.outerHTML
-    // it create a bug where new body or new head are created in the dom
-    // if you set head.outerHTML, a new body tag is appended, so the dom get 2 body
-    // & it break the switchFallback which replace head & body
-    if (!this.options.switches.head) {
-      this.options.switches.head = this.switchElementsAlt
-    }
-    if (!this.options.switches.body) {
-      this.options.switches.body = this.switchElementsAlt
-    }
-
+    var parseOptions = require("./lib/proto/parse-options.js");
+    parseOptions.apply(this,options)
     this.log("Pjax options", this.options)
 
-    if (typeof options.analytics !== "function") {
-      options.analytics = function() {}
-    }
+    this.maxUid = this.lastUid = newUid()
 
     this.parseDOM(document)