Add URLs for captive portal tests

[hellais]

Some people were interested in having the list of URLs that some vendors use to detect the presence of captive portals.

We have this information inside of the ooniprobe captive portal test.

I will paste the important text in here:

# This test is a collection of tests to detect the presence of a
# captive portal. Code is taken, in part, from the old ooni-probe,
# which was written by Jacob Appelbaum and Arturo Filastò.
#
# This module performs multiple tests that match specific vendor captive
# portal tests. This is a basic internet captive portal filter tester written
# for RECon 2011.
#
# Read the following URLs to understand the captive portal detection process
# for various vendors:
#
# http://technet.microsoft.com/en-us/library/cc766017%28WS.10%29.aspx
# http://blog.superuser.com/2011/05/16/windows-7-network-awareness/
# http://isc.sans.org/diary.html?storyid=10312&
# http://src.chromium.org/viewvc/chrome?view=rev&revision=74608
# http://code.google.com/p/chromium-os/issues/detail?3281ttp,
# http://crbug.com/52489
# http://crbug.com/71736
# https://bugzilla.mozilla.org/show_bug.cgi?id=562917
# https://bugzilla.mozilla.org/show_bug.cgi?id=603505
# http://lists.w3.org/Archives/Public/ietf-http-wg/2011JanMar/0086.html
# http://tools.ietf.org/html/draft-nottingham-http-portal-02
#

        vendor_tests = [['http://www.apple.com/library/test/success.html',
                         'Success',
                         '200',
                         'Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420+ (KHTML, like Gecko) Version/3.0 Mobile/1A543a Safari/419.3',
                         'Apple HTTP Captive Portal'],
                        ['http://tools.ietf.org/html/draft-nottingham-http-portal-02',
                         '428 Network Authentication Required',
                         '428',
                         'Mozilla/5.0 (Windows NT 6.1; rv:5.0) Gecko/20100101 Firefox/5.0',
                         'W3 Captive Portal'],
                        ['http://www.msftncsi.com/ncsi.txt',
                         'Microsoft NCSI',
                         '200',
                         'Microsoft NCSI',
                         'MS HTTP Captive Portal', ]]