refactoring - remove query indents duplication via pulling up string properties to AbstractQuery
typo fix in Select query test
add Query\Pgsql\Delete with RETURNING feature
add Query\Pgsql\Insert with RETURNING feature
add Query\Pgsql\Update with RETURNING feature
add Query\Pgsql\Select with no features yet, but for complete picture for PgSQL
Merge pull request #53 from MAXakaWIZARD/pr-pgsql-query-objects

PgSQL Query objects