d/libnss-unknown.nss: Use dh_installnss instead of handwritten maintscripts (Closes: #1024690)

Gioele Barabuccirequested to merge
gioele/libnss-unknown:use-dh-installnss into master

dh_installnss provides a declarative way to install NSS services.

In comparison to the existing scripts, dh_installnss also handles DPKG_ROOT and various edge-cases such as invalid /etc/nsswitch.conf files, database lines with comments, etc.

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