commands: gensdkshell: Extend to make it usable from outside
commands: gensdkshell: Extend to make it usable from outside

This will allow other commands or any component to generate shell script
to set env variables

+ Set python and gtk env variable if variants are activated

atsushieno/cerbero,ikonst/cerbero,GStreamer/cerbero,nzjrs/cerbero,fluendo/cerbero,jackjansen/cerbero,atsushieno/cerbero,lubosz/cerbero,flexVDI/cerbero,OptoFidelity/cerbero,ikonst/cerbero,fluendo/cerbero,multipath-rtp/cerbero,GStreamer/cerbero,nzjrs/cerbero,flexVDI/cerbero,shoreflyer/cerbero,ford-prefect/cerbero,jackjansen/cerbero,sdroege/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,centricular/cerbero,ramaxlo/cerbero,ramaxlo/cerbero,AlertMe/cerbero,nirbheek/cerbero,shoreflyer/cerbero,fluendo/cerbero,nzjrs/cerbero,fluendo/cerbero,atsushieno/cerbero,multipath-rtp/cerbero,centricular/cerbero,ford-prefect/cerbero,GStreamer/cerbero,ramaxlo/cerbero,atsushieno/cerbero,brion/cerbero,nzjrs/cerbero,superdump/cerbero,EricssonResearch/cerbero,flexVDI/cerbero,flexVDI/cerbero,AlertMe/cerbero,ikonst/cerbero,EricssonResearch/cerbero,jackjansen/cerbero,multipath-rtp/cerbero,nirbheek/cerbero-old,ford-prefect/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,multipath-rtp/cerbero,flexVDI/cerbero,ramaxlo/cerbero,OptoFidelity/cerbero,sdroege/cerbero,nirbheek/cerbero,AlertMe/cerbero,nirbheek/cerbero-old,sdroege/cerbero,sdroege/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,GStreamer/cerbero,AlertMe/cerbero,centricular/cerbero,justinjoy/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,nirbheek/cerbero,shoreflyer/cerbero,EricssonResearch/cerbero,justinjoy/cerbero,centricular/cerbero,justinjoy/cerbero,brion/cerbero,nzjrs/cerbero,lubosz/cerbero,superdump/cerbero,brion/cerbero,ford-prefect/cerbero,lubosz/cerbero,justinjoy/cerbero,EricssonResearch/cerbero,brion/cerbero,superdump/cerbero,EricssonResearch/cerbero,GStreamer/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,centricular/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,sdroege/cerbero,nirbheek/cerbero-old,freedesktop-unofficial-mirror/gstreamer__cerbero,atsushieno/cerbero,jackjansen/cerbero,ikonst/cerbero,nirbheek/cerbero,OptoFidelity/cerbero,shoreflyer/cerbero,superdump/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,brion/cerbero,ramaxlo/cerbero,AlertMe/cerbero,lubosz/cerbero,fluendo/cerbero,shoreflyer/cerbero,multipath-rtp/cerbero,nirbheek/cerbero-old,OptoFidelity/cerbero,ikonst/cerbero