Check automatic variable availability

In comparing the Preference Variables documentation for PowerShell 6.x and newer:
https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_preference_variables?view=powershell-6

to the Preference Variables documentation for PowerShell 5.1:
https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_preference_variables?view=powershell-5.1

it seems that a number of Preference Variables were removed/deprecated from PowerShell. I just ran into this problem unexpectedly on a script when testing it on PowerShell 6.x.

To help with this problem, I would like the PSUseCompatibleCommands feature of PSScriptAnalyzer to flag the usage of deprecated Preference Variables and state that they are not compatible with PowerShell 6.0 and newer (on any platform including Windows).

首先比较链接的 PowerShell 6.x 和 5.1 的 about_Preference_Variables 文档，然后在 PSScriptAnalyzer 中定位 PSUseCompatibleCommands 功能。完成标准是：对已弃用的 preference-variable 用法进行标记，并说明其在所有平台上都与 PowerShell 6.0 及更高版本不兼容。