Is your feature request related to a problem? Please describe.
It would be useful to be able to set a property from a registry key.

Describe the solution you'd like

<property name="content" registry="HKEY_LOCAL_MACHINE\SOFTWARE\7-Zip\Path64" />

Describe alternatives you've considered
N/A

Additional context
This feature would allow people to detect software installation directory. These values are usually stored in the registry. For example, 7-zip installation directory is defined in the registry key HKEY_LOCAL_MACHINE\SOFTWARE\7-Zip\Path64. The property should read the key and set the value of the property from the registry key value.

An advanced use case would be to define a 7-zip (or any other software) Configuration File that can be easily shared across multiple users.

<?xml version="1.0" encoding="utf-8"?>
<root>
  <shell>
    <default>
      <!-- Detect 7-zip installation directory from the registry -->
      <property name="sevenzip.dir" registry="HKEY_LOCAL_MACHINE\SOFTWARE\7-Zip\Path64" />
    </default>

    <menu name="7-zip">
      <visibility properties="sevenzip.dir" />

      <menu name="Compress to *.7z">
  	<visibility maxfiles="1" maxfolders="0" />
        <actions>
          <exec ... />
        </actions>
      </menu>

    </menu>
  </shell>
</root>