Move amber stuff from JobRecord

Hi,

This is my (barbarous) effort to remove the AmberDb stuff out of JobRecord.  It doesn't get autowired inside of JobRecord and you get NullPointerExceptions when you try and use it.

Instead the JobsController passes the AmberSessions to the JobRecord.  This is probably subverting some kind of a design pattern but it works.

@terenceingram this fixes the NullPointerExceptions you were reporting.

@scoen @JonathanShaw

Huw