Adds API unit tests and modifies bitcoin_sim to be fixture compatible

- Adds unit tests for API
- Updates API to let BlockProcessor deal with block block related JSON-RPC
- Fixes BlockProcessor get_potential_matches return
- Makes bitcoin_sim runnable via function (instead of a main runnable script) to work with pytests fixture
- <3 Fixture

pisa/block_processor.py

@@ -56,6 +56,8 @@ class BlockProcessor:
         else:
             logging.info("[BlockProcessor] no potential matches found")
 
+        return potential_matches
+
     @staticmethod
     def get_matches(potential_matches, locator_uuid_map, appointments):
         matches = []