qtwayland: switch repository to github.com/mer-packages

We're using the qtwayland version from the Mer project which is on top of latest upstream
qtwayland but contains a lot of usefull modifications to support a libhybris based
scenario.

Signed-off-by: Simon Busch <morphis@gravedo.de>
libsdl: add version preliminary version 2.0 with wayland support

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
rm_old_work: drop WORKDIR modification

* it's no longer needed, package.bbclass was fixed to package source
  correctly when last directory ends with just PV and this layout is also
  default in oe-core now

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Drop cmake 2.8.7 in favour of newer version from oe-core

Signed-off-by: Simon Busch <morphis@gravedo.de>
WIP: base-files: add dirty workaround to provide XDG_RUNTIME_DIR