Improve SQL Server migration process

[labkey-adam]

Rationale

Test SQL Server migration process and fix some minor issues.

Fix a variety of SimpleFilter issues that arose during the cloning migration work. Add regression tests for these issues.

IN (NULL) has been used in various places as a substitute for FALSE. This construct is problematic because NULL is considered an unknown value in SQL, which means IN (NULL) evaluates to FALSE and NOT IN (NULL) also evaluates to FALSE, which can lead to surprising results. For LabKey, new InClause(fk, emptyList) selects no rows and new NotClause(new InClause(fk, emptyList)) also selects no rows.

Changes

• Fix SQLClause.equals()
• Eliminate DatabaseMigrationConfiguration.getColumnNameFilter(); each configuration's getTableSelector() method can filter columns, if needed.
• Bootstrap Users and Guests groups during migration. Delete them before migration.
• BasePostgreSqlDialect is common to Redshift and PostgreSQL; move PostgreSQL-specific methods from BasePostgreSqlDialect to PostgreSql92Dialect.
• Fix SqlDialect.testLikeOperator() when scopes with different dialects are present. All configured scopes are tested, but the debug string used by the test was always generated assuming the LabKey scope.
• Replace use of IN (NULL) to represent FALSE with 0 = 1