Problem: ZMQ_ZERO_COPY_RCV not marked as DRAFT in docs

Solution: update manpages

doc/zmq_ctx_get.txt

@@ -43,6 +43,7 @@ ZMQ_ZERO_COPY_RCV: Get message decoding strategy
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 The 'ZMQ_ZERO_COPY_RCV' argument return whether message decoder uses a zero copy
 strategy when receiving messages. Default value is 1.
+NOTE: in DRAFT state, not yet available in stable releases.
 
 
 ZMQ_SOCKET_LIMIT: Get largest configurable number of sockets

doc/zmq_ctx_set.txt

@@ -134,6 +134,7 @@ use a zero copy strategy when receiving messages. The zero copy strategy can
 lead to increased memory usage in some cases. This option allows you to use the
 older copying strategy. You can query the value of this option with
 linkzmq:zmq_ctx_get[3] using the 'ZMQ_ZERO_COPY_RECV' option.
+NOTE: in DRAFT state, not yet available in stable releases.
 
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 Default value:: 1