ISIS-657,ISIS-660,ISIS-661,ISIS-662,ISIS-663,ISIS-667,ISIS-668,ISIS-670: JDO services

ISIS-657:
- appsettings / usersettings entities also now use "Isis" as prefix to table names

ISIS-660:
- renamed InteractionFactory to InteractionService
- renamed InteractionRepository to InteractionServiceJdoRepository
- InteractionDefault and InteractionJdo now have a next() method, to create sequences of numbers
  (as used to generate the PKs for PublishedEventJdo and BackgroundTaskJdo, see below)
- Interaction#startedAt renamed to Interaction#timestamp (and #startedAt now a derived property)
- Interaction now defines a #transactionId property
- IsisTransaction now picks up its transactionId from passed-in Interaction object (if available)
  - and defers to Interaction for generation of next pub/sub event sequence if it can (else previous behaviour)
- IsisTransaction#guidId renamed to #transactionId


ISIS-661: (background service mementos, background task service)
- renamed BackgroundTaskContributions to BackgroundTaskServiceJdoContributions
- renamed BackgroundTaskRepository to BackgroundTaskServiceJdoRepository

ISIS-662: published events contributions
- renamed PublishedEventRepository to PublishingServiceJdoRepository
- renamed PublishedEventContributions to PublishingServiceJdoContributions


ISIS-663: audit entry contributions
- rename AuditEntryCountributions to AuditingServiceJdoContributions
- rename AuditEntryRepository to AuditingServiceJdoRepository

ISIS-667:
- added JdoColumnLength as central location for standard column lengths of JDO entities
- renamed AuditEntry to AuditEntryJdo
- renamed PublishedEvent to PublishedEventJdo
- changed PK for PublishedEventJdo entity to be application-defined: (transactionId,sequence)
- change to datatype of some PublishedEventJDO entities
- changed PK for BackgroundTaskJdo entity to be application-defined: (transactionId,sequence)
- factored out Util class for JDO entities
- renamed UserSettingPrimaryKey to UserSettingJdoPK

ISIS-668:
- improvements to ServicesInstallerFromConfiguration
- improved formatting of isis.properties in the todo app & simple app

ISIS-670:
- removed AuditingService, AuditingService2 APIs
- introduced replacement AuditingService3 API