cf_subshell_scoped_login: export target env variable.
cf_subshell_scoped_login: export target env variable.

This can then be used to add an indicator to your shell prompt to
indicate which CF env you're targetting. eg:

PS1='\u@\h:\w${CF_SUBSHELL_TARGET+ (cf-$CF_SUBSHELL_TARGET)}\$ '

alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf