[superceded by #1477]: Course and Resources API

[panaaj]

This PR is based on server v1.41 and superscedes #1361 to implement the following:

• Course API as outlined in Signal K specification PR #629.
• Request handling for the Signal K ./api/resources path for both defined resource types (routes, waypoints, notes, regions and charts) and user defined types.
• Resources API for the creation, and updating of resources (./api/resources/set/<resource_type>)
• Interface for Resource Provider plugins to persist resource data.

Features:

• GET, PUT, POST and DELETE request processing for /signalk/v1/api/resources and /signalk/v1/api/resources/*paths
• Validation of submitted resource data for Signal K defined resource types.
• Interface for plugins to retrieve resources (getResource(type, id))
• Interface for plugins to register as a Resource Provider
• Populates both courseGreatCircle and courseRhumbline attributes
• Provides a single path to get destination information (./navigation/course)
• Persists destination information so it is not lost if server is restarted
• Backward compatibility with exisiting plugins

Resource Provider Plugins:
The persistance of resource data to a storage device is performed by a resource provider plugin.
In this way plugins can be written to support different storage types i.e. filesystem files, database or remote storage.

Example: Filesystem based Resource Provider plugin

[panaaj]

@tkurki I have created this new branch / PR which is based on v1.41 release.

The one issue I encountered is that with the changes to some of the type definitions I can no longer define the passed app instance as extending both Application and SignalKMessageHub due to emit having different declarations.

I'm not sure if this was intended or just a side-effect of the type refinement?

Extending SignalKMessageHub is required to get the

signalk: FullSignalK
handleMessage: (id: string, data: any) => void

declarations.
Previously these declarations were declared in WithSignalK which is what was being used prior to the changes.

I have worked around it for now by having the declarations in the local file.

interface ResourceApplication
  extends Application,
    WithSecurityStrategy {
      handleMessage: (id: string, data: any) => void
    }

[tkurki]

Some comments

[tkurki]

I'd be bold enough to put this under v2. What do you think? @sbender9 ?

[panaaj]

Removed calling clearDestination() on setActiveRoute() / setDestination() error