Make sure to have a hardware integration when creating windows

We need to do a full roundtrip and wait for the qt_hardware_integration
global before returning from QWaylandDisplay constructor. Waiting
for the screen is not enough, since there is no guarantee it will come
after the hardware integration global.

Change-Id: I34cb50b830632db7e5d5c7a502eeef778599b267
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Bind the globals with the highest version available

Change-Id: I639b124f15416905c17665755b3288c905880f39
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Wait to get wl_output's events before creating surfaces

Change-Id: I2eb4b40a4b8b1de7990d06b57b0d7a7b04ee9657
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Add a way to have out of source shell integrations

Some platforms (especially non-desktop ones) may use a custom
Wayland shell extension, more tailored to the form factor than
the generic and desktoppy wl_shell or xdg_shell. Instead of stuffing
N protocol implementations in the QPA plugin use a plugin architecture
to allow them to live out of tree.
When creating a shell surface the QT_WAYLAND_SHELL_INTEGRATION env
variable will be checked, and if it points to a valid plugin that
will be used to create the shell surface, falling back to wl_shell
or xdg_shell if no plugin is specified.

Change-Id: I05019174bb915199dd726f5fdcc0385ef846e8de
Reviewed-by: Pier Luigi Fiorini <pierluigi.fiorini@gmail.com>
Reviewed-by: Philippe Coval <rzr@gna.org>
Reviewed-by: Jan Arne Petersen <jan.petersen@kdab.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Fix namespaced build

Change-Id: Id73f8ddffe00359f38c634fc88b1f81ac5638653
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>