🔧 Configure PSScriptAnalyzer for the project #5

- Added the following settings files to the root folder:
  + `PSScriptAnalyzerSettings.psd1`
  + `PSScriptAnalyzerSettings.desktop-3.0-windows.psd1`
- Enabled `PSUseCompatibleCmdlets` and `PSUseCompatibleSyntax` rules to
  ensure the scripts are compatible with the target PowerShell version
  + `PSScriptAnalyzerSettings.psd1`: PowerShell 2.0 or higher
  + `...desktop-3.0-windows.psd1`: PowerShell 3.0 to 5.0 desktop version

Fixes [#5](#5)

Author: chriskyfung

PSScriptAnalyzerSettings.desktop-3.0-windows.psd1

@@ -0,0 +1,22 @@
+@{
+  Severity = @('Error', 'Warning')
+  Rules = @{
+    PSUseCompatibleCmdlets = @{
+      Compatibility = @(
+        'desktop-3.0-windows'
+        'desktop-4.0-windows'
+        'desktop-5.1.14393.206-windows'
+      )
+    }
+    PSUseCompatibleSyntax = @{
+      TargetedVersions = @(
+        '6.0'
+        '5.1'
+        '4.0'
+        '3.0'
+        '2.0'
+      )
+    }
+  }
+  ExcludeRules = @('PSAvoidUsingWriteHost')
+}

PSScriptAnalyzerSettings.psd1

@@ -0,0 +1,24 @@
+@{
+  Severity = @('Error', 'Warning')
+  Rules = @{
+    PSUseCompatibleCmdlets = @{
+      Compatibility = @(
+        'desktop-2.0-windows'
+        'desktop-3.0-windows'
+        'desktop-4.0-windows'
+        'desktop-5.1.14393.206-windows'
+        'core-6.1.0-windows'
+      )
+    }
+    PSUseCompatibleSyntax = @{
+      TargetedVersions = @(
+        '6.0'
+        '5.1'
+        '4.0'
+        '3.0'
+        '2.0'
+      )
+    }
+  }
+  ExcludeRules = @('PSAvoidUsingWriteHost')
+}