Import libasr-1.0.2 as net/libasr. Based on
PR pkg/51106 by ISIHARA Takanori.
libasr is a FREE asynchronous DNS resolver.
libasr runs on top of the OpenBSD operating system but also has a portable
version that can build and run on several systems, including:
* Linux
* FreeBSD
* NetBSD
* DragonFly
* MacOSX
(mef)