Fix randomized metadata ($DATE in gdp image definition name)

Oscar provided a PR #130.

Problem:

Currently the genivi-dev-platform bb file defines the component as genivi-dev-platform, with PV = "1.3+snapshot-${DATE}" This means it changes everytime. Rebuilding the platform in the same directory will cause a lot of warnings due to the version having changed its name.

Discussion/decisions:

1. I suggested that the GDP commit hash should be used for unambiguous definition. That should only change if something new is checked out, which probably makes sense?

2. The question of what major version we should use also came up. No one seems to quite know where "1.3" comes from but it's apparently not something we have updated in the past.

Moving the discussion from GitHub PR to here since it seems to involve some discussion and agreement on design decisions.

AC

• Decide on solution and document how/when we bump up the version number
• Implement and merge change to the relevant recipes