UPDATE

 By insisting I'll post the code to load more than one file at a time:

In the http.py file must comment a line and add another, in the line 608:

http.py

class HttpRequest(WebRequest):
    """ Handler for the ``http`` request type.

    matched routing parameters, query string parameters, form_ parameters
    and files are passed to the handler method as keyword arguments.

    In case of name conflict, routing parameters have priority.

    The handler method's result can be:

    * a falsy value, in which case the HTTP response will be an
      `HTTP 204`_ (No Content)
    * a werkzeug Response object, which is returned as-is
    * a ``str`` or ``unicode``, will be wrapped in a Response object and
      interpreted as HTML

    .. _form: http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2
    .. _HTTP 204: http://tools.ietf.org/html/rfc7231#section-6.3.5
    """
    _request_type = "http"

    def __init__(self, *args):
        super(HttpRequest, self).__init__(*args)
        params = self.httprequest.args.to_dict()
        params.update(self.httprequest.form.to_dict())
        #params.update(self.httprequest.files.to_dict())
        params.update(self.httprequest.files) # Modified line
        params.pop('session_id', None)
        self.params = params 

My controller:

from openerp import http
import simplejson
import time
import os
import StringIO


class Binary_Multi(http.Controller):

    @http.route('/web/binary/multi_picture_upload', type="http", auth="public")
    def multi_picture_upload(self, req, callback, ufile):
        out = """<script language="javascript src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js" type="text/javascript">
                    var win = window.top.window;
                    win.jQuery(win).trigger(%s, %s);
                        </script>"""
        args = []
        for nfile in ufile:
                    data = nfile.read()
                    current_dat_time = time.strftime("%d-%m-%Y-%H_%M_%S")
                    file_name = current_dat_time + "_" + nfile.filename
                    addons_path = http.addons_manifest['web']['addons_path'] +\
                        "/web/static/src/img/image_multi/"
                    if not os.path.isdir(addons_path):
                        os.mkdir(addons_path)
                    addons_path += file_name
                    buff = StringIO.StringIO()
                    buff.write(data)
                    buff.seek(0)
                    file_name = "/web/static/src/img/image_multi/" + file_name
                    file = open(addons_path, 'wb')
                    file.write(buff.read())
                    file.close()
                    args.append([len(data), file_name, nfile.content_type,
                                nfile.filename, time.strftime("%m/%d/%Y %H:%M:%S")])
        return out % (simplejson.dumps(callback), simplejson.dumps(args)) 

 Now you can scroll through the list with for loop

but this would cause us a problem, if we upload attachments in fields.Binary.

I modify the core again to use both, my multiple images fields and traditional fields.Binary attachments.

class HttpRequest(WebRequest):
    """ Handler for the ``http`` request type.

    matched routing parameters, query string parameters, form_ parameters
    and files are passed to the handler method as keyword arguments.

    In case of name conflict, routing parameters have priority.

    The handler method's result can be:

    * a falsy value, in which case the HTTP response will be an
      `HTTP 204`_ (No Content)
    * a werkzeug Response object, which is returned as-is
    * a ``str`` or ``unicode``, will be wrapped in a Response object and
      interpreted as HTML

    .. _form: http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2
    .. _HTTP 204: http://tools.ietf.org/html/rfc7231#section-6.3.5
    """
    _request_type = "http"

    def __init__(self, *args):
        super(HttpRequest, self).__init__(*args)
        params = self.httprequest.args.to_dict()
        params.update(self.httprequest.form.to_dict())
        #params.update(self.httprequest.files.to_dict())
        
        str_args = str(args)
        # If the request is from my controller,( in tis case, multi_picture_upload)then use modified line
        if str_args.find("multi_picture_upload") >=0: # 
            params.update(self.httprequest.files)
        # Else, just use the original line
        else:
            params.update(self.httprequest.files.to_dict())
        params.pop('session_id', None)
        self.params = params 

sorry that my code is so ugly/akward, and my English so bad.