avoid instance var warnings + make sure we do not test again if not true
db2 on as400: force decimal field with 0 scale to be integers because they dont have integer datatypes when creating tables from rpg and because saving a decimal in that field fails because ruby always seems to puts a .0 on in the end of the field
adding ordering support when using both limit and offset
Check if offset is set, otherwise use the Arel::Node::Offset#expr method to retrieve offset value

Signed-off-by: Jason Franklin <franklin@equinux.com>
tweak h2 offset test to only run on AR 3.0+
(also do not use users table as they might collide when full suite run)
it's probably better to load java parts from adapter where code is defined
mostly due re-use - previously H2 was failing since it needs HSQLDB functionality implemented on it's java side but it requires only the adapter part of HSQLDB (no connection method are being loaded)
Ignoring encoding option in pg, printing warning about it. Fixes #376
Don't call set_client_encoding from configure_connection
[postgres] some more notes on client_encoding + set search path once