configs: bump GUI build to Qt5

Qt4 based builds are no longer supported
qt5webkit: make 'discovery' and 'accelerated canvas' configurable

instead of 'always on' the options can now be disabled
qt5webkit: correct .mk to use configurable options
qt5webkit: correct .mk, add  options to WEBKIT_CONFIG
qt5webkit: disable 'accelerated canvas' in non-OpenGL builds
rpi-userland: bump to latest version
rpi-firmware: bump to latest version
rpi: bump to kernel 3.10.36
qtbrowser: bump to version 1.0.4
rpi-firmware: bump to latest version