[PATCH] mpr: Implement WNetClearConnections().

[Pierre Schweitzer]

Hi,

Please find attached a patch implements an undocumented Windows MPR API
that is used on logoff to disconnect any network share connection.
Implementation based on:
https://git.reactos.org/?p=reactos.git;a=blob;f=base/applications/network/ne...
Successfully tested in: https://jira.reactos.org/browse/CORE-15012

Cheers,