[NEW] net/lua-psl

Hi ports@,

Here is a new port: net/lua-psl

Comments? OK?

From DESCR:

Lua bindings to libpsl, a C library that handles the Public Suffix List.

The PSL is a list of domains where there may be sub-domains outside of the
administrator's control. e.g. the administrator of '.com' does not manage
'github.com'.