- use php7 type-hints
-
edit "Session2DB->use_lock_via_mysql(bool|null)"
- true => use mysql GET_LOCK() / RELEASE_LOCK()
- false => use php flock() + LOCK_EX
- null => use mysql + extra lock-table
- add "Session2DB->use_lock_via_mysql(bool)"
- use new version of "Simple MySQLi" (voku/simple-mysqli)
- drop support for PHP < 7.0
- use "strict_types"
- add a interface && a wrapper class for the database-connection