Temporary fix to generic_send (exporting env variables)
Temporary fix to generic_send (exporting env variables)

 - we don't want to export some environmental variables to the endpoint
 - SendEnv set in ssh_cofig cannot be overwritten
 - so we send them rather empty, for this purpose we need to unset them
 - affected variables are LC_TIME and LANG
 - it is just temporary fix, better solution is to create separate ssh_config

frhrdina/perun-services,sustr4/perun-services,sustr4/perun-services,stavamichal/perun-services,zlamalp/perun-services,frhrdina/perun-services,sustr4/perun-services,CESNET/perun-services,zlamalp/perun-services,CESNET/perun-services,zlamalp/perun-services,CESNET/perun-services,sustr4/perun-services,CESNET/perun-services,frhrdina/perun-services,zlamalp/perun-services,stavamichal/perun-services,stavamichal/perun-services,stavamichal/perun-services,frhrdina/perun-services