rewrite integer check function to allow specifying a minimum value

for flushing the results

It is more consistent with existing naming within erp5.util and
zope.testbrowser parent module as well.

account

fix also parameter name for password tool

check must be done on email address part only, not the formatted address

remove check which are done by the form

- add validator with error message
- fix field name

The most long test takes about 1h only, so it is more them enough delay.

Just a silly conditional mistake.

Explain what shall be returned by server.

Follow new way of POSTing instead of putting.

If data are posted twice with the same coordinates only one data set document
is begin created, not two. This was changed in 33a5a2be

return empty string by default