Add a mock for absolute_url as the test requires a valid url

 Those values shouldn't be applied on production

slapos_payzen; Scripts moved to slapos_account in order to make it compatible with multiple payment types

slapos_accouting: Scripts moved from slapos_payzen to make it compatible with multiple payment types

For now Payzen and Wechat

Depending on the netifaces version the netmask can come with or without
lenght prefix, so support both cases and consider netmask with prefix
as equal to without prefix.

The only result will be update of the netmask in the computer XML file.

self.interface.getGlobalScopeAddressList which uses netifaces can have
different sorting of the addresses depending of the version, so prefer the
already configured IPv6 address.

According to this [code](https://lab.nexedi.com/nexedi/slapos.core/blob/master/master/bt5/slapos_jio/PathTemplateItem/web_page_module/rjs_gadget_erp5_page_slap_computer_view_js.js#L127) . I believe the test `testSlapOSJSServer` currently failed due to a typo. There may have other failing in this test, but at least we can fix this one first.

/reviewed-on nexedi/slapos.core!165

This isn't the most suitable script for this anymore or some extra configurations can be used.

mostly copied from slapos_payzen

In Gitlab,  if URL is like https://USERNAME:PASSWORD@somedomain.com then gitlab will return 401 and ask for basic Authentication.

For this kind of URL, we simply extract username and password and send ajax request with Basic Auth.

/reviewed-on nexedi/slapos.core!163

follow up of f2798c25

it was still crashing when "create_tap = True"

add erp5_accounting to fix the following:
runTestSuite: Adding erp5_configurator business template ... (imported in 1.134s) (missing dependencies : ['erp5_accounting']) done (5.681s)

add a test to see if all BT are correctly installed

Also renames it so it reflects well its function.

Before the fix in 77c4cca0b3026fb6b35c13d2bb7cc1b43ae1da26, each call
to /loadComputerConfigurationFromXML was deleting all the partition in
the database. After the fix, because the test environment is not cleaned
correctly between different tests, some slapparts would remain between
following tests.
Thanks to this commit, the previous behavior is restaured.

loadComputerConfigurationFromXML must be idempotent : if partitions are requested the
same, then nothing should be done.
With this commit, we make sure we only delete partitions that don't exist anymore,
create new ones, and update the remaining ones

* --token ask in "slapos configure client" is not supported ("ask" is interpreted
     as the argument value, iow the token)
   * node_name : a node name is an unknown concept. On slapos.vifib.com interface, the
     nodes have titles and references

/reviewed-on nexedi/slapos.core!158

fix the following crash in command ```slapos node boot``` in slapos package version "1.5.2+1.0.125+3-1" :

```
# slapos node boot
[BOOT] Checking if 'lo' has IPv6...
[BOOT] Invoking ipv6 ping to slap.vifib.com...
[BOOT] IPv6 network reachable...
[BOOT] Invoking slapos node format...
2019-11-20 09:43:52 slapos[5511] WARNING Creating new computer data with id 'COMP-3121'
2019-11-20 09:43:52 slapos[5511] INFO Adding 10 new partitions
2019-11-20 09:43:52 slapos[5511] INFO Updating computer
2019-11-20 09:43:52 slapos[5511] ERROR u'ffff:ffff:ffff:ffff:ffff:ffff::/96' is not a valid IPv6 address string!
Traceback (most recent call last):
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/cli/entry.py", line 300, in run_subcommand
    result = cmd.run(parsed_args)
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/cli/command.py", line 50, in run
    return self.take_action(parsed_args)
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/cli/format.py", line 128, in take_action
    do_format(conf=conf)
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/format.py", line 1401, in do_format
    use_unique_local_address_block=conf.use_unique_local_address_block)
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/format.py", line 665, in format
    partition.address_list.append(self.interface.addIPv6Address())
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/format.py", line 1227, in addIPv6Address
    if self._addSystemAddress(addr, netmask, tap=tap):
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/format.py", line 1058, in _addSystemAddress
    address_string = '%s/%s' % (address, netmaskToPrefixIPv6(netmask))
  File "/opt/slapos/eggs/slapos.core-1.5.2-py2.7.egg/slapos/format.py", line 179, in netmaskToPrefixIPv6
    netaddr.strategy.ipv6.str_to_int(netmask)]
  File "/opt/slapos/eggs/netaddr-0.7.19-py2.7.egg/netaddr/strategy/ipv6.py", line 142, in str_to_int
    raise AddrFormatError('%r is not a valid IPv6 address string!' % addr)
AddrFormatError: u'ffff:ffff:ffff:ffff:ffff:ffff::/96' is not a valid IPv6 address string!
[BOOT] [ERROR] Fail to format, try again in 15 seconds...
[BOOT] Invoking slapos node format...
```

/reviewed-on !157

The leading spaces in the XML will lead the XML to become invalid

/reviewed-on nexedi/slapos.core!153

It is the most used value in most scenarios.