Redesign the way processors are identified; fixes #653 #705

Job	Run time
windows-msvc-shared (CBOR)	1m 27s
windows-msvc-shared (AVRO)	7m 14s
windows-msvc-shared (PARQUET)	38m 29s
windows-msvc-shared (TOML)	2m 33s
windows-msvc-shared (BOOST_SERIALIZATION)	7m 18s
windows-msvc-shared (XML)	2m 25s
windows-msvc-shared (FLEXBUFFERS)	5m 29s
windows-msvc-shared (CAPNPROTO)	7m 52s
windows-msvc-shared (JSON)	12m 18s
windows-msvc-shared (MSGPACK)	5m 27s
windows-msvc-shared (YAML)	3m 1s
windows-msvc-shared (UBJSON)	3m 39s
windows-msvc (TOML)	2m 41s
windows-msvc (CEREAL)	4m 33s
windows-msvc (UBJSON)	3m 50s
windows-msvc (AVRO)	7m 14s
windows-msvc (MSGPACK)	3m 51s
windows-msvc (CAPNPROTO)	8m 56s
windows-msvc (BOOST_SERIALIZATION)	8m 8s
windows-msvc (YAML)	3m 20s
windows-msvc (CBOR)	8m 39s
windows-msvc (PARQUET)	9m 19s
windows-msvc (FLEXBUFFERS)	5m 32s
windows-msvc (benchmarks)	43m 13s
windows-msvc (JSON)	12m 4s
windows-msvc (XML)	2m 53s
	3h 41m 25s

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