Move msgpack value classes to another project msgpack-value#571

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dmikurube wants to merge 5 commits intomsgpack:mainfrom

dmikurube:split-msgpack-value-abstract-MessagePacker

Commits on May 18, 2021

Add a subproject msgpack-value
Dai MIKURUBE
committed
Move value classes to project msgpack-value
Dai MIKURUBE
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Clone org.msgpack.core.MessagePack.Code to org.msgpack.value.MessagePackCode
Dai MIKURUBE
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Move MessageFormat, MessageFormatException, MessagePackException, MessageTypeException and MessageTypeCastException to msgpack-value
Dai MIKURUBE
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Split MessagePacker to abstract in msgpack-value and implementation in msgpack-core
Dai MIKURUBE
committed