Incremented version and changed UV due to limits

iChrome has been exceeding UserVoice's free plan limits (1,000,000
requests/month).  This change makes the auto-prompt code only load for
20% of page views.

This commit also increments the version, and moves the homepage override
up in the manifest so merges don't have to be handled manually.

app/js/core/uservoice.js

@@ -2,34 +2,46 @@
  * Initializes UserVoice and it's autoprompts
  */
 define(["core/uid"], function(uid) {
-	window.UserVoice = window.UserVoice || [];
+	var initUV = function() {
+		var uv = document.createElement("script");
 
-	var uv = document.createElement("script");
+		uv.async = true;
+		uv.type = "text/javascript";
+		uv.src = "https://widget.uservoice.com/YLT6rl3u3uU75IbSodIBw.js";
 
-	uv.async = true;
-	uv.type = "text/javascript";
-	uv.src = "https://widget.uservoice.com/YLT6rl3u3uU75IbSodIBw.js";
+		var s = document.getElementsByTagName("script")[0];
 
-	var s = document.getElementsByTagName("script")[0];
+		s.parentNode.insertBefore(uv, s);
 
-	s.parentNode.insertBefore(uv, s);
+		window.UserVoice.push(["set", {
+			accent_color: "#448dd6",
+			trigger_color: "white",
+			screenshot_enabled: "false",
+			trigger_background_color: "rgba(46, 49, 51, 0.6)"
+		}]);
 
-	window.UserVoice.push(["set", {
-		accent_color: "#448dd6",
-		trigger_color: "white",
-		screenshot_enabled: "false",
-		trigger_background_color: "rgba(46, 49, 51, 0.6)"
-	}]);
+		window.UserVoice.push(["identify", {
+			id: uid
+		}]);
 
-	window.UserVoice.push(["identify", {
-		id: uid
-	}]);
+		window.UserVoice.push(["autoprompt", {
+			position: "toast"
+		}]);
+	};
+
+	if (Math.random() * 5 < 1) {
+		window.UserVoice = window.UserVoice || [];
 
-	window.UserVoice.push(["autoprompt", {
-		position: "toast"
-	}]);
+		initUV();
+	}
 
 	return function() {
+		if (!window.UserVoice) {
+			window.UserVoice = [];
+
+			initUV();
+		}
+
 		window.UserVoice.push(Array.prototype.slice.call(arguments));
 	};
 });

app/manifest.json

@@ -40,6 +40,9 @@
 		"48": "icon/48.png",
 		"128": "icon/128.png"
 	},
+	"chrome_settings_overrides": {
+		"homepage": "http://ichro.me/redirect"
+	},
 	"permissions": [
 		"storage",
 		"topSites",
@@ -56,10 +59,7 @@
 		"bookmarks",
 		"management"
 	],
-	"chrome_settings_overrides": {
-		"homepage": "http://ichro.me/redirect"
-	},
-	"version": "2.1.17",
+	"version": "2.1.18",
 	"manifest_version": 2,
 	"default_locale": "en",
 	"short_name": "iChrome",