Add additional status individuals to support publisher activities

[rjyounes]

In addition to bib:current, we need one to represent "first/earliest" and one for "intermediate/intervening". Dates are not always present so in that case the order must be derived from the status.

Robert Rendell: In correctly cataloged records you will have:

one 260/264 with first indicator blank
zero or one 260/264 with first indicator 3
zero or any number of 260/264s with first indicator 2

If there is a 260/264 with first indicator 3, that's the current or most recent publication statement. If not, the 260/264 with first indicator blank is the current or most recent publication statement.

[rjyounes]

LC mappings ignore this info, so maybe we don't want to represent it.