# increment current, and set revision to 0.
# 5. If any interfaces have been added since the last public release, then increment age.
# 6. If any interfaces have been removed since the last public release, then set age to 0.
# increment current, and set revision to 0.
# 5. If any interfaces have been added since the last public release, then increment age.
# 6. If any interfaces have been removed since the last public release, then set age to 0.