Windows Shell Integration: Use the QLocalSocket on windo and do the request assynchroniously

Squashed commit of the following:

commit 4d9b072f560fa171a1390b7c74425614aa20e955
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Tue Oct 14 16:04:02 2014 +0200

    Remove useless variable

commit 8e85de0307ec5f31bf3f92a7de793fed7d41c2ea
Author: Daniel Molkentin <danimo@owncloud.com>
Date:   Tue Oct 14 16:01:52 2014 +0200

    Make Windows Explorer Extension build

commit 8e2942cd9fd32e3af72d60cba0d06bd9d6222a45
Author: Daniel Molkentin <danimo@owncloud.com>
Date:   Tue Oct 14 11:39:37 2014 +0200

    Fix compilation

commit 0fc0c0e0e0c7e58ad97f62700256c7d1f8c0670b
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Tue Oct 14 11:48:32 2014 +0200

    Windows Shell Integration: Try to let the thread notify about changes when there are changes

commit 4a1712b7c03269ca3007f167b8f313ea47655967
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Tue Oct 14 11:35:20 2014 +0200

    Windows Shell Integration: Share the RemotePathChecker amongst all the OCOverlay instances

commit 2d87408e9af5a4d7ab71c460ce606ba1f367c09f
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Mon Oct 13 18:55:15 2014 +0200

    Windows Shell Integration: Attempts to wait on multiple objects (WIP)

commit e448e427b6d1561ad7a40d08fc6632f4d2b4ef44
Author: Daniel Molkentin <danimo@owncloud.com>
Date:   Mon Oct 13 17:58:02 2014 +0200

    Introduce a worker thread

commit 2344407ec0bc1ce173ebbacadcf3992d62d94078
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Mon Oct 13 17:03:47 2014 +0200

    Windows Shell Integration:  try to keep the socket open using a thread (WIP)

commit ea6d5273ed60d8bc3f1c5d5c6936364d783a1c0f
Author: Daniel Molkentin <danimo@owncloud.com>
Date:   Mon Oct 13 15:27:46 2014 +0200

    Make Explorer plugin work again with named pipes

    This is a temporary hack, which needs more refactoring.

commit 44a3437a44082379efa0078c9afd7b8bbde930de
Author: Daniel Molkentin <danimo@owncloud.com>
Date:   Sat Oct 11 07:31:24 2014 +0200

    Fix code

commit 123390a0f3516c0078309d7048c6d2acb9293676
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Fri Oct 10 16:29:35 2014 +0200

    Windows shell integration: Use named pipe  (WIP)

commit 9eea7e2321abeac6b8db0bd85bfce612dbf6bb20
Author: Olivier Goffart <ogoffart@woboq.com>
Date:   Wed Oct 1 12:04:13 2014 +0200

    Windows Shell Integration: Simplify StringUtil

    This fixes a memory leak in CommunicationSocket::ReadLine