Extended model

Added a new  data provider 'M.DataProviderRemoteStoragePaginated' for remote paginated filtered searchs.

Added a 'count' function to the model.

Example of M.DataProviderRemoteStoragePaginated:
Declaring the provider:
```javascript
M.MetroMixProvider = M.DataProviderRemoteStoragePaginated.configure({
'NotaCreditoDetail': {
		url: '/metroMixServer/notasCredito',
		read: {
			url: {
				all: function() {
					return '';
				},
				paginated: function(firstResult, maxNumberResults, filter) {
					return "/" + filter + "/amount/" + firstResult + "/" + maxNumberResults;
				}
			}, 
			
			// mapeo necesario para devolver un objeto que pueda ser manejado por createRecord
			map: function(obj) {
				
				return {
					fechaEmision: M.Date.create(obj.fechaEmision), 
					valor: obj.valor
				};
				
			}
		},
		count: {
			url: {
				all: function() {
					return '/count';
				},
				filter: function(filter) {
					return '/' + filter + '/count';
				}
			}
		},
		beforeSend : function(xhr) {
			var config = M.Application.getConfig('authorization');
			var encodedUserPass = M.Base64.encode(config.username + ':' + config.password);
			xhr.setRequestHeader('Authorization', config.type + ' ' + encodedUserPass);
		}
	}
});
```
Using the provider:

```javascript
        M.LoaderView.show(M.I18N.l('loading_list') + '...');
    	var obj = {
        		firstResult: 0,
        		maxNumberResults: 20,
        		filter: 'typeA',
        		onSuccess: function(model) {
        			
        			var controller = MmxMobile.NotasCreditoDetailController;
        			controller.set('results', model);
        			M.LoaderView.hide(); 
        		},
        		onError: function(error) {
        			M.LoaderView.hide();
        			alert(M.I18N.l('connection_problem') + ": " + error.xhr.status + " (" + error.xhr.statusText + "). " + error.xhr.responseText);
				}
        };
        MmxMobile.NotaCreditoDetail.find(obj); // a request is sent to: /metroMixServer/notasCredito/typeA/amount/0/20
```

Spanish wiki: https://github.com/avantic/The-M-Docs/wiki/DataProviderRemoteStorage

As soon as we can, we'll translate the wiki to english, and we'll add it to the 'GitHub' pages of The-M-Docs.