Manage listings

gps --package com.example.app --json listings list
gps --package com.example.app listings get en-US

gps --package com.example.app listings update en-US \
  --title "My App" \
  --short-description "Short pitch under 80 chars" \
  --full-description "Longer description..." \
  --confirm

gps call gps_list_images '{
  "packageName": "com.example.app",
  "language": "en-US",
  "imageType": "phoneScreenshots"
}'