Upgraded to PHPUnit 8.1.6 and reworked the remaining driver exception mock

Allow Symfony 5

add .github/FUNDING.yml

Deprecated Driver::getName()

The method is not used for anything else than skipping tests for specific drivers. Cross-driver portability should be established by drivers, not outside of them based on their name.

Removed 2.8 from README

Removed the rest of mock classes

The usage of user-provided PDO instance is deprecated

Default column expressions do not work on SQL Server

Removed the assertion which doesn't work with a user-provided PDO connection

Reworked driver exception tests

1. Got rid of hard-coded exception mocks in favor of PHPUnit-generated ones where possible.
2. Reworked AbstractDriverTest::testConvertsException() to use a data provider to make testing all types of exceptions independent.
3. Updated PHPUnit since the reworked code relies on sebastianbergmann/phpunit#3604.

Deprecate the public constants in SQLParserUtils

Deprecate SQLSrvStatement::LAST_INSERT_ID_SQL constant.

Improve ExceptionTest::testConnectionExceptionSqLite

on linux running as root.

Reworked SQL Server installer on Travis CI

Handle default values as values, not SQL expressions

Maintain platform parameter in connection params

Expand list of keywords in composer.json

using params in query cache key generation.

Extract constants for built-in types from Type to Types

Extract type factory and registry from Type into TypeRegistry

Enabled the build against IBM DB2 on PHP 7.3 on Travis CI