Adding ZmMetaData to store public keys in SQL instead of LDAP. This seemed a good idea,
but it is also limited to much and slow.

Public keys 1-30 are stored in Zimbra LDAP and have maximum length of 5120 chars. Public keys 31-40 are stored in Zimbra SQL and have a combined maximum length of 32768 chars.

Right now I moved the password from LDAP to SQL, seemed	a bit more secure, need	to investigate this more.
Also to-do: make all LDAP files show emtpy for new users so 'undefined' text string does not get stored to the server.
Same way as been done for the SQL fields.