Base Widget Support

[Jack-Byrne]

This PR adds changes required to RPCs that were introduced by the widgets proposal.

This pr does not add widget functionality to the generic HMI, these are only minimal changes required for the HMI to work with Core 6.0.0.

Updates:

• Deprecate SetDisplayLayout
• Update show request to handle template configurations
• Add text supported to soft button capabilities
• Update Capabilities structure
• Add OnSystemCapabilityUpdated notification to core

[iCollin]

I have a question about the getWindowCapability(template) function:

It's main client is BCController.js when handling the OnAppRegistered RPC, where it seems to be called with either MEDIA or NON-MEDIA template based on rpc.params.application.isMediaApplication.

Neither of these templates in DisplayCapabilities.js have softButtonCapabilities or buttonCapabilities within the displayCapabilities object.

Therefore, won't the return of this function always have a null buttonCapabilities and softButtonCapabilities?

[Jack-Byrne]

@iCollin Good catch. My mistake here was thinking softbutton capabilities was included in the displayCapabilities json object.