Add keychain package

packages/keychain.rb

+require 'package'
+
+class Keychain < Package
+  description 'Keychain helps you to manage SSH and GPG keys in a convenient and secure manner.'
+  homepage 'https://www.funtoo.org/Keychain'
+  version '2.8.5'
+  source_url 'https://github.com/funtoo/keychain/archive/2.8.5.tar.gz'
+  source_sha256 'dcce703e5001211c8ebc0528f45b523f84d2bceeb240600795b4d80cb8475a0b'
+
+  binary_url ({
+  })
+  binary_sha256 ({
+  })
+
+  def self.install
+    system "gzip -9 keychain.1"
+    system "install -Dm755 keychain #{CREW_DEST_PREFIX}/bin/keychain"
+    system "install -Dm644 keychain.1.gz #{CREW_DEST_PREFIX}/share/man/man1/keychain.1.gz"
+    system "mkdir -p #{CREW_DEST_PREFIX}/share/keychain"
+    system "rm -f .gitignore keychain keychain.1.gz keychain.spec.in keychain.spec keychain.pod Makefile"
+    system "cp -r . #{CREW_DEST_PREFIX}/share/keychain"
+  end
+end