asteroid.conf: Disable at the distro level the meta-gnome's warning of not using x11 which appeared with meta-openembedded sumo

Add a 'hybris-watch' machine configuration include file that factorizes code between each watch configuration. Also include a new PREFERRED_PROVIDER_virtual/mesa line to close https://github.com/AsteroidOS/asteroid/issues/76

initramfs-android-image: Provide a default ANDROID_EXTRA_INITRAMFS_IMAGE_INSTALL at the distro level to fix builds after recent meta-smartphone updates

Remove Mesa 10.3.7 whose LLVMPipe is not compatible with OE Rocko's new LLVM version. Prepare a switch from VBox+VBoxGuestAdditions to QEMU+VirGL3D

Fixes usage of FILESYSTEM_PERMS_TABLES which fixes the owner of /home/ceres/.config and services relying on this directory such as dconf, solving wallpaper/watchfaces changing

Removes qtconnectivity_experimental.bb which is not needed anymore since asteroid-btsyncd is implemented over BlueZ's GATT DBus API

Setup permissions so that timed can change time: includes changing the connman's dbus allowing policy, adding a postinst script ran at boot to add CAP_SYS_TIME to timed-qt5 and add xattr to the DISTRO_FEATURES so that setcap is compiled

Set QT_DIR_NAME to an empty string so that Qt specific binaries are no longer installed in odd not-in-PATH places like /usr/bin/qt5/. It also removes the need for some ugly sed hacks. Cf: https://github.com/meta-qt5/meta-qt5/blob/master/classes/qmake5_paths.bbclass

Factorizes code from asteroid-image and asteroid-image-dev in the asteroid distro and the asteroid-image.bbclass