Iterate all keys in any given section
Iterate all keys in any given section

This undoes what appears to be a mistake in
7ac43c777ffa3ffa2289ed299a2369b32adb8146.

This also avoids the breaking change introduced by that commit wherein
only one key may be removed per section.

saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt