Release v 1.2

[nbundi]

changelog:

Added terminationDate as state variable
Aligned Execution and Exercise terminology
Aligned fixingDays, settlementPeriod, gracePeriod, ... terminology
Added enum options with identifier, name and description
Added maturityDate state variable. fixed default value of maximumPenaltyFreeDisbursement. Fixed typos.
Added underlying contract roles UDL, UDLP, UDLM
Added ‘matured’ and ‘terminated’ contract performance values
Fixed various typos
Merged Event Types and Event sheets into Event table that contains types as allowed values for the Event Type field
Fixed contract structure term and added option and acronym to contract structure role and type enums
Updated Period and Cycle types to the ISO8601 Duration standard
Fixed missing options in the contractPerformance state variable