Refactor code structure for improved readability and maintainability (#473)

* Add ToolTips to Tweaks

Scripts/FileIO/SaveCustomAppsListToFile.ps1

@@ -0,0 +1,15 @@
+# Saves the provided appsList to the CustomAppsList file
+function SaveCustomAppsListToFile {
+    param (
+        $appsList
+    )
+
+    $script:SelectedApps = $appsList
+
+    # Create file that stores selected apps if it doesn't exist
+    if (-not (Test-Path $script:CustomAppsListFilePath)) {
+        $null = New-Item $script:CustomAppsListFilePath -ItemType File
+    }
+
+    Set-Content -Path $script:CustomAppsListFilePath -Value $script:SelectedApps
+}