RPCDaemon: support Pending block (#1942)

* clean

* save

* pubsub

* pubsub

* pubsub

* pubsub

* pubsub

* pubsub

* save

* tx pub-sub

* tx pub-sub

* clean

* clean

* save

* save

* save

* save

* save

* Squashed 'interfaces/' content from commit c469f3ae0

git-subtree-dir: interfaces
git-subtree-split: c469f3ae073b60c8821b61fed2910191080ef835

* save

* save

* save

* save

* Squashed 'interfaces/' changes from c469f3ae0..958dfc669

958dfc669 save

git-subtree-dir: interfaces
git-subtree-split: 958dfc669f8daeefe686a13aa852fb95f1537886

* save

* save

* up some deps

* up some deps

* clean

* test

* test

* test

* test

* test

* test

* test

* test

* test

* test

* test

* test