entryID should not be a field on Video Object

[flipmcf]

The canonical way to get the entry id should be 'object.entryId'

The 'backend' way to get the entry id should be 'object.KalturaObject.getId()' - but this shouldn't be used under normal circumstances.

object.entryId getter (dexterity) needs to be created and used, and should under most circumstances, simply call 'object.KalturaObject.getId()' and handle all exceptions that may occur due to that call.

This was the behavior in rfa.kaltura in Archetypes.
https://github.com/RadioFreeAsia/rfa.kaltura/blob/9eb2a48178280bafbb1c2c665bd74ab14f99ceb6/rfa/kaltura/content/base.py#L12
https://github.com/RadioFreeAsia/rfa.kaltura/blob/9eb2a48178280bafbb1c2c665bd74ab14f99ceb6/rfa/kaltura/content/base.py#L108

This caused a bug that was just fixed by this commit:
3b87589