Remove getaddrinfo and freeaddrinfo from the Libc::Plugin and get rid of
the extra libc_resolv library. Remove getaddrinfo/freeaddrinfo symbol
hiding patch for FreeBSD sources. Remove libc_resolv from Makefiles and
run scenarios.
Fix#2273
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082