fix($resource): Route constructor, updated RegExp

Update RegExp to allow urlParams with out leading slash (/).
- Will allow reoucese to be loaded from a relative path

Example:
var R = $resource(':path');
R.get({ path : 'data.json' });

Example usage:
Load resources in applications not using webserver, ie local webapp in on a tablet.

src/ngResource/resource.js

@@ -290,7 +290,7 @@ angular.module('ngResource', ['ng']).
       this.defaults = defaults || {};
       var urlParams = this.urlParams = {};
       forEach(template.split(/\W/), function(param){
-        if (param && template.match(new RegExp("[^\\\\]:" + param + "\\W"))) {
+        if (param && (new RegExp("((\\w|\\/|^)(?!\\\\:" + param + ")):" + param + "\\W")).test(template)) {
           urlParams[param] = true;
         }
       });

test/ngResource/resourceSpec.js

@@ -129,6 +129,12 @@ describe("resource", function() {
     R.get({a: 'doh@fo o', ':bar': '$baz@1', '!do&h': 'g=a h'});
   });
 
+  it('should allow relative paths in resource url', function () {
+    var R = $resource(':a');
+    $httpBackend.expect('GET', 'data.json').respond('{}');
+    R.get({ a: 'data.json' });
+  });
+
 
   it('should encode & in url params', function() {
     var R = $resource('/Path/:a');