Force tarantool client to use bufferization for IO
Add patched FindPostgreSQL.cmake that just works

CMake is shipped with broken PosgreSQL script in most distros.
I had to copy this script and patch it to properly support
new versions of PostgreSQL.
Add pg and mysql dependecies to travis
Add missing postgresql-server-dev dependecy for Debian

Needed for server/pg_type.h header
Use postgresql-server-dev-all package for server/pg_type.h
Merge remote-tracking branch 'origin/opentar-69' into stable
Merge branch 'stable'

Conflicts:
	.travis.yml
	client/tarantool/tc.c
	client/tarantool/tc_pager.c
	src/lua/yaml.cc