dev-lang/janet: new package

dev-lang/janet: new package

Janet is a functional and imperative programming language and bytecode
interpreter. It is a modern lisp, but lists are replaced by other data
structures with better utility and performance (arrays, tables, structs,
tuples). The language also supports bridging to native code written in C,
meta-programming with macros, and bytecode assembly.

Package-Manager: Portage-2.3.84, Repoman-2.3.16
Signed-off-by: Oz Tiram <oz.tiram@gmail.com>
Closes: https://github.com/gentoo/gentoo/pull/14503
Signed-off-by: Joonas Niilola <juippis@gentoo.org>