MINIFI-235: Resolve hostname ident

[phrocker]

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[randerzander]

Tested this in CentOS7 in docker, as well as from one physical host to another. All works as expected using shortnames and fqdns.

[phrocker]

@randerzander big thanks for testing this for me!

[jdye64]

reviewing

[jdye64]

Tested using official MiNiFi Docker image against official NiFi Docker image running on Mac OS X host. Was able to successfully transfer flowfiles from minifi to nifi using fqdn where previously only ip address worked. Thanks @randerzander for pointing that out and @phrocker for the quick fix.