Merge pull request #154 from lucasvr/lucas/mdns-cache-flag #460

Job	Run time
build_and_test (rustcrypto)	4m 36s
build_and_test (rustcrypto, alloc)	4m 25s
build_and_test (rustcrypto, os)	6m 14s
build_and_test (mbedtls)	4m 41s
build_and_test (mbedtls, alloc)	4m 43s
build_and_test (mbedtls, os)	6m 35s
build_and_test (openssl)	4m 28s
build_and_test (openssl, alloc)	4m 31s
build_and_test (openssl, os)	5m 55s
	46m 8s

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