Add price record state field

This field works as follows:
1. When CSV import starts, all records state is set to 'updating'.

2. Then on import new records are inserted or old records are upded with
state 'active'

3. When importing done - all records with state 'updating' are changed
to state 'inactive'

Option selection wizard uses 'active' and 'updating' fields and not 'inactive'
fields
Enable admin for pricelist models
Initial pricelist views