Fix package dependency

Fixed dependency definition of RPM SPEC file.

Change version to 3.9.11

Bumped up version to 1.3.10

Bumped up version to 1.3.10

Update spec files.

Update rpm spec files for 1.3.9 release.

Version bumped up to 1.3.8.

Mainly for management reasons, version of pg_dbms_stats bumped up to
1.3.8. Since no functional changes has taken place, the change is made
only for the PostgreSQL 10 build. Other builds will be bumped up in
the future releases if any.

Update copyright notice

Update copyright notices in several files that have left unchaged so
far.

Support for 9.4 added officially.

Since PostgreSQL REL9_4_0 has been released, pg_dbms_stats became to
support 9.4. There's no functional change made and some fixes in the
steps to build RPM packages has been made.

Change release number of spec files to 2.

The previous release was based on the funcion-version of
HeapTupleGetDatum() so they cannot be loaded on the minor versions
earlier than 9.1.14, 9.2.9 and 9.3.5 with link failure of
HeapTupleHeaderGetDatum.

I confirmed that the commit(*1) does not affect pg_dbms_stats and
decided to build rpm releases on 9.1.13, 9.2.8 and 9.3.4 after this.

There has been one bug after 1.3.5 was released but it is a bug in
error message of rarely used SQL function so no increment of version
number.

*1: d3c9f9c5b57d2a8a7ab065a6b942703854ec5e97 for 9.1
    315442c01156d4f6c0f766ec51da090a613d03b8 for 9.2
    edde59db1339397ec389d45e4c0d0f86064dad1a for 9.3
    621a99a666ba1a27b852dc5ddc0e1b224c388f53 on master branch

Update RPM release number to 2.

Edit RPM spacfiles and ChangeLogs