Re: SQL:2011 application time

I fixed your tests, some of your tests can be simplified, (mainly
primary key constraint is unnecessary for the failed tests)
also your foreign key patch test table, temporal_rng is created at
line 141, and we use it at around line 320.
it's hard to get the definition of temporal_rng. I drop the table
and recreate it.
So people can view the patch with tests more easily.

+ <para>
+ In a temporal foreign key, the delete/update will use
+ <literal>FOR PORTION OF</literal> semantics to constrain the
+ effect to the bounds being deleted/updated in the referenced row.
+ </para>

in v24-0003-Add-temporal-FOREIGN-KEYs.patch
<literal>FOR PORTION OF</literal> not yet implemented, so we should
not mention it.

+ <para>
+ If the last column is marked with <literal>PERIOD</literal>,
+ it must be a period or range column, and the referenced table
+ must have a temporal primary key.
can we change "it must be a period or range column" to "it must be a
range column", maybe we can add it on another patch.