Let ptVault.setAgePublic accept ptVaultAgeInfoNode in addition to ptAgeInfoStruct.

In this case it now also works for non-owners of the age. Previously it only worked for owners because the ageInfoStruct does not contain the vault node ID, so it needed to be looked up somewhere, and that was in the AgesIOwnFolder.
Merge pull request #461 from cwalther/setpublic

Let ptVault.setAgePublic accept ptVaultAgeInfoNode in addition to ptAgeInfoStruct