- add move special member functions (docs copied from QHostInfo)
- add member swap
- use move-and-swap, not pure-swap, because these objects hold
resources (handles) other than just memory
- Q_DECLARE_SHARED (it's not implicitly shared, but explicitly)
- adds ADL swap and Q_DECLARE_TYPEINFO
[ChangeLog][QtOpenGL][QOpenGLBuffer] Added member-swap(), move
constructor, move assignment operator.
Change-Id: I22dc92108bdd393fff4361db23e94eaf3d7ea9cc
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>