11.0.0: New connection semantics

• Merged PR #46: Remove flags "unbuffered", "storeresult", "persistent"
  and "newlink":
  • Unbuffered queries are run by using open() instead of query() and are
    definitely not a per-connection flag
  • Persistent connections were dropped completely - they have caveats
    regarding locks and transactions described in the PHP Manual here:
    http://php.net/manual/en/features.persistent-connections.php
  • Creating new links is the default now, instantiating two DBConnection
    instances and not creating a new connection seems counter-intuitive
    (@thekid)
• Merged PR #45: Default reconnect to 1 - @thekid
• Merged PR #47: Remove unused affectedRows() method - @thekid
• Merged PR #48: Remove deprecated classes - @thekid