adjust examples from README to match new substreams-eth-block-meta ke…

…y format

README.md

@@ -46,10 +46,10 @@ It exposes this data through Connect-Web protocol (compatible with GRPC)
 
 (these commands have been tested while running the 'devel/local/start.sh' in another terminal)
 
-* Get single block data: `grpcurl --plaintext   -d '{"key":"72e08a117f596b31ae49bda6f093c2d812e64f69bb3d5aab2f4f47fdaea0c512"}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetMany`
-* Get many: `grpcurl --plaintext   -d '{"keys":["72e08a117f596b31ae49bda6f093c2d812e64f69bb3d5aab2f4f47fdaea0c512","72e046b07eb0263277e3a5e5968d60810273f74a1e8ef64c9b3bf522285accc8"]}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetMany`
-* By prefix: `grpcurl --plaintext   -d '{"prefix": "ffa", "limit":100}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetByPrefix`
-* Scan: `grpcurl --plaintext   -d '{"begin": "ffff46b07eb0263277e3a5e5968d60810273f74a1e8ef64c9b3bf522285accc8", "exclusive_end": "ffffb5738d3f365313963d49af78f08e1953623189bea23d5ed3562a55f8d165", "limit":3}' localhost:8000 sf.substreams.sink.kv.v1.Kv/Scan`
+* Get single block data: `grpcurl --plaintext   -d '{"key":"month:last:201511"}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetMany`
+* Get many: `grpcurl --plaintext   -d '{"keys":["day:first:20151201","day:first:20151202"]}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetMany`
+* By prefix: `grpcurl --plaintext   -d '{"prefix": "day:first:201511", "limit":31}' localhost:8000 sf.substreams.sink.kv.v1.Kv/GetByPrefix`
+* Scan: `grpcurl --plaintext   -d '{"begin": "day:first:201501", "exclusive_end": "day:first:2016", "limit":400}' localhost:8000 sf.substreams.sink.kv.v1.Kv/Scan`
 
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