Add rakudo.eclass and dev-raku/*

rakudo.eclass requires install-dist.raku installed by a modified version
of dev-lang/rakudo. Gentoo overlay's dev-lang/rakudo doesn't install
install-dist.raku.

rakudo.eclass is minimal and elegant. dev-raku/* packages depend on
rakudo.eclass.

Signed-off-by: amano.kenji <amano.kenji@proton.me>

dev-raku/Shell-Command/Manifest

@@ -0,0 +1 @@
+DIST Shell-Command-0_pre20190129.tar.gz 4078 BLAKE2B 5ea7ea986f7d0594124270fc7824499d4bc0e005743645a9c5c8488c6e6b31538fafb9c36b5dc46771dd3c617bd288440ffba3a0bc9deb12f5809a3ee9da5d3c SHA512 12096f58e7760b28fde51c95fe18be4b881aa2799691d739d5731c8fee239e964cacaef10af150185c1ce2d8c422e25a10c849eb6487d27dde9dedafbf4daa9f

dev-raku/Shell-Command/Shell-Command-0_pre20190129-r1.ebuild

@@ -0,0 +1,21 @@
+# Copyright 2020-2022 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI="8"
+
+inherit rakudo
+
+COMMIT="1145ea0ff71507b2fe932fca6d2a68d4004c7d12"
+
+DESCRIPTION="Cross-platform routines emulating common *NIX shell commands"
+HOMEPAGE="https://github.com/tadzik/Shell-Command"
+SRC_URI="https://github.com/tadzik/Shell-Command/archive/${COMMIT}.tar.gz -> ${P}.tar.gz"
+LICENSE="MIT"
+SLOT="0"
+KEYWORDS="~amd64"
+RESTRICT="primaryuri"
+DOCS="README.md"
+RDEPEND="dev-raku/File-Find
+	dev-raku/File-Which"
+DEPEND="${RDEPEND}"
+S="${WORKDIR}/${PN}-${COMMIT}"

dev-raku/Shell-Command/metadata.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
+<pkgmetadata>
+</pkgmetadata>