This reverts commit 185ddf09.

This reverts commit 623b55f1.

lxml web site, provided by index, is not functional for long time (weeks).
As it is possible to install it directly form pypi (which has a bit of
mirroring) force such way and do not query source website.

This reverts commit 97268ab6.
kumo : No need to hardcode more.

erp5testnode is not fully stable yet, we often need to
update it, we don't need to fix everything right now
This reverts commit 7f251b0c.