Console: getting rid of redundant Loader code
LIVEOAK-512: Console: Better use of subscriptions
Merge pull request #343 from vrockai/LOADER

LIVEOAK-512: Console: Better use of subscriptions
Introduce ResourceSink.error(Throwable)
Rename ResourceSink.close() to ResourceSink.complete()

 - The changed name better reflects what the method does,
 - removing AutoCloseable prevents using try-with-resources which is an anti-pattern in this case since catch has to be performed before closing the sink.
Convert Resources into SynchronousResources as appropriate, and fix current implementations
 - convert readProperties() / readMembers() / readMember() to properties() / members() / member()
Convert additional Resources into SynchronousResource as appropriate
Add error() to PropertySink, and convert additional Resources to SynchronousResource as appropriate
Merge pull request #344 from mstruk/LIVEOAK-573

LIVEOAK-573 Common pattern violation using ResourceSink
LIVEOAK-580 Change SynchronousResource.properties() to return Map