Add enscript package and libpth dependency

Add pre-built binaries

packages/enscript.rb

+require 'package'
+
+class Enscript < Package
+  description 'GNU Enscript is a free replacement for Adobe\'s enscript program.'
+  homepage 'https://www.gnu.org/software/enscript/'
+  version '1.6.6'
+  source_url 'https://ftpmirror.gnu.org/enscript/enscript-1.6.6.tar.gz'
+  source_sha256 '6d56bada6934d055b34b6c90399aa85975e66457ac5bf513427ae7fc77f5c0bb'
+
+  binary_url ({
+    aarch64: 'https://dl.bintray.com/chromebrew/chromebrew/enscript-1.6.6-chromeos-armv7l.tar.xz',
+     armv7l: 'https://dl.bintray.com/chromebrew/chromebrew/enscript-1.6.6-chromeos-armv7l.tar.xz',
+       i686: 'https://dl.bintray.com/chromebrew/chromebrew/enscript-1.6.6-chromeos-i686.tar.xz',
+     x86_64: 'https://dl.bintray.com/chromebrew/chromebrew/enscript-1.6.6-chromeos-x86_64.tar.xz',
+  })
+  binary_sha256 ({
+    aarch64: '316ed484d08cfbe16632937379a05366b9841e986e351fd3d4061f474e046725',
+     armv7l: '316ed484d08cfbe16632937379a05366b9841e986e351fd3d4061f474e046725',
+       i686: '4332bbf72b8622a2ecbc84e58f55b1515ce66c3d678c69c1f28402cfc6e2a7e3',
+     x86_64: '638519de1bdfc08816d511f8ad468213d78293a77a26295630a0266b664582c9',
+  })
+
+  depends_on 'libpth'
+
+  def self.build
+    system './configure',
+           "--prefix=#{CREW_PREFIX}",
+           "--libdir=#{CREW_LIB_PREFIX}",
+           '--disable-maintainer-mode'
+    system 'make'
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end

packages/libpth.rb

+require 'package'
+
+class Libpth < Package
+  description 'Pth is a very portable POSIX/ANSI-C based library for Unix platforms'
+  homepage 'https://www.gnu.org/software/pth/'
+  version '2.0.7'
+  source_url 'https://ftpmirror.gnu.org/pth/pth-2.0.7.tar.gz'
+  source_sha256 '72353660c5a2caafd601b20e12e75d865fd88f6cf1a088b306a3963f0bc77232'
+
+  binary_url ({
+    aarch64: 'https://dl.bintray.com/chromebrew/chromebrew/libpth-2.0.7-chromeos-armv7l.tar.xz',
+     armv7l: 'https://dl.bintray.com/chromebrew/chromebrew/libpth-2.0.7-chromeos-armv7l.tar.xz',
+       i686: 'https://dl.bintray.com/chromebrew/chromebrew/libpth-2.0.7-chromeos-i686.tar.xz',
+     x86_64: 'https://dl.bintray.com/chromebrew/chromebrew/libpth-2.0.7-chromeos-x86_64.tar.xz',
+  })
+  binary_sha256 ({
+    aarch64: '6df029d8c9a59cc6bfba3308d362589b5d32e72fecc282dfb6e05e67fac6c387',
+     armv7l: '6df029d8c9a59cc6bfba3308d362589b5d32e72fecc282dfb6e05e67fac6c387',
+       i686: '49344c2b2eafe8f4490b94bed951b8e7eb31bb45c358d21f531fcd9741e412c6',
+     x86_64: 'b82687dc8d4525dd8deee18576ae9ffbb149c2a7a378de68db60fd12de3f6b12',
+  })
+
+  def self.build
+    system './configure',
+           "--prefix=#{CREW_PREFIX}",
+           "--libdir=#{CREW_LIB_PREFIX}",
+           '--enable-optimize'
+    system 'make'
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end