[DBAL-1014] Support HHVM mysqli driver

Close #696

[DBAL-1009] Fix column comment lifecycle

[DBAL-1001] Fix NULL / NOT NULL clause for column alterations in Oracle

[DBAL-831] Fix explicit case sensitive identifiers in Oracle

[Documentation] Add missing quotes at the end of literal strings

[DBAL-1010] Fix renaming column with default value on SQL Server

[DBAL-1011] Fix column comments containing string literal chars on SQL Server

Fixed expanding positional parameters which do not start from 0

Add test for explicit positional parameter keys in SQLParserUtils

Changed the composer constraint to allow Common 2.5

[DBAL-774] Fix QueryBuilder parsing order of joins

Clean up unused uses

avoid recursive quoteIdentifier call

each $part does not contain ".", so quoteSingleIdentifier may be called directly thus avoiding recursive strpos checks.

[DBAL-959] Allow to get bound parameter types from query builder