Add powershell package (#3994)

Add xdg_base dependency

packages/powershell.rb

+require 'package'
+
+class Powershell < Package
+  description 'Powershell is a cross-platform, task-based command-line shell and scripting language that helps rapidly automate tasks that manage operating systems and processes'
+  homepage 'https://docs.microsoft.com/en-us/powershell/'
+  version '7.0.0'
+  case ARCH
+  when 'aarch64', 'armv7l'
+   source_url 'https://github.com/PowerShell/PowerShell/releases/download/v7.0.0/powershell-7.0.0-linux-arm32.tar.gz'
+   source_sha256 'cbb6acbb40f73ccf83920f4729dc86ebf3566bb9a01ca68e0698d33fdbe6d7b0'
+  when 'x86_64'
+    source_url 'https://github.com/PowerShell/PowerShell/releases/download/v7.0.0/powershell-7.0.0-linux-x64.tar.gz'
+    source_sha256 '3e80a662a5defb283185961330c4a44d5d5179f9eb2a2ee74ac7e1d3caf16b2c'
+  end
+
+  depends_on 'xdg_base'
+
+  def self.install
+    FileUtils.mkdir_p "#{CREW_DEST_PREFIX}/bin"
+    FileUtils.mkdir_p "#{CREW_DEST_PREFIX}/share/powershell"
+    FileUtils.cp_r Dir.glob('.'), "#{CREW_DEST_PREFIX}/share/powershell"
+    FileUtils.ln_s "#{CREW_PREFIX}/share/powershell/pwsh", "#{CREW_DEST_PREFIX}/bin/pwsh"
+  end
+
+  def self.postinstall
+    puts
+    puts "To get started, execute 'pwsh'".lightblue
+    puts
+  end
+end