rename gst-launch --> gst-launch-1.0
replace old elements with new elements(ffmpegcolorspace -> videoconvert, ffenc_** -> avenc_**)
fix caps in examples
https://bugzilla.gnome.org/show_bug.cgi?id=759432
Previously the different decoders would discard errounous GstFlowReturns coming
from downstream. Now we properly return these further upstream so that we
properly error out on eg. negotiation problems.