Merge pull request #34 from dbeck/master

exception forwarding from the async worker of connector clients
Updated gtest submodule.
update gtest ref
Updated submodule
update submodules
update submodule ref
update submodule ref
fix makefile
Copied files from virtdb-enterprise
add suport for STATUS loglevel
Fixes while integrating to Postgres FDW
fix allocation of nulls vector
update submodule ref
Updated gtest. Fixed column subscription channel and adding filters to queries.
Merge remote-tracking branch 'origin/master' into engine-to-common
Merge pull request #35 from starschema/engine-to-common

Engine to common
restructuring engine related libs
moving engine lib into virtdb::engine namespace
fix Malefile for MacOSX
restructuring engine lib to log more detailed information