To open a command prompt in any directory in Windows Explorer, follow these steps to add a list item to the context menu:

• Open up Windows Explorer
• Click “Tools” -> “Folder Options” -> “File Types”
• Select the “Folder” file type
• Click “Advanced” -> “New…”
• The Action will be displayed on the context.  For example, I entered “PowerShell Here”.
• Now enter “C:\Windows\system32\WindowsPowerShell\v1.0\powershell.exe  -NoExit -Command Set-Location -LiteralPath ‘%L’” for the program to use or “C:\Windows\system32\cmd.exe” if you don’t have PowerShell installed.

If you want to later remove the entry from your menu and the “Remove” and “Edit…” buttons are grayed out as they were for me then you can open up regedit and delete the corresponding entry from HKEY_CLASSES_ROOT/FOLDER/shell