Fix invalid inversion domain to use None instead of False

issue3681
review4891004
(grafted from ad93806d5d8f4b3b8fa39e39fdfc956319b84022)

--HG--
branch : 2.8
extra : source : ad93806d5d8f4b3b8fa39e39fdfc956319b84022
Sort child screen as unsaved records

Child screen could contains records added using the add_remove of one2many and
so those records must be managed as unsaved.

issue3835
review5001002
(grafted from 4c577ef09d3c3fcfe4388763c256993c9ca44a22)

--HG--
branch : 2.8
extra : source : 4c577ef09d3c3fcfe4388763c256993c9ca44a22
Always convert datetime from client to UTC

issue3857
review5201002
(grafted from e7719ce99d5d6ca977f61bc26e15fb132e7b7857)

--HG--
branch : 2.8
extra : source : e7719ce99d5d6ca977f61bc26e15fb132e7b7857
Convert only non-empty datetime from client to UTC

issue3866
review5261002
(grafted from 20c4b6c559e5f7f20405dc39d99f3e61c6c6bab5)

--HG--
branch : 2.8
extra : source : 20c4b6c559e5f7f20405dc39d99f3e61c6c6bab5
Fix parameter inversion in 'not in' domain inversion

issue3849
review5131002
(grafted from 5097d1681816d55f1a828b1af9c5996c4aea2ec2)

--HG--
branch : 2.8
extra : source : 5097d1681816d55f1a828b1af9c5996c4aea2ec2
Prepare release 2.8.7

--HG--
branch : 2.8
Added tag 2.8.7 for changeset 26477fa7d54e

--HG--
branch : 2.8
Increase version number

--HG--
branch : 2.8