[New Package] which (#4925)

packages/which.rb

+require 'package'
+
+class Which < Package
+  description 'which shows the full path of (shell) commands.'
+  homepage 'https://carlowood.github.io/which/'
+  version '2.21'
+  compatibility 'all'
+  source_url 'https://carlowood.github.io/which/which-2.21.tar.gz'
+  source_sha256 'f4a245b94124b377d8b49646bf421f9155d36aa7614b6ebf83705d3ffc76eaad'
+
+  def self.build
+    system "./configure #{CREW_OPTIONS}"
+    system "make"
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+
+  def self.check
+    system "make", "check"
+  end
+end