Since our DLLs version number aren't bumped, a same file size could
cause a DLL not to be installed to replace an old one.
This eventually can cause a crash of explorer if an incompatible version
of OCUtil.dll is installed alone.

Fix the issue by defining LIBRARY_IGNORE_VERSION. This also makes sure
that installing an old version of the client over a more recent one
if we decide to add version numbers to those DLLs.

This would cause a full sync every 30 seconds.

(cherry picked from commit bacf6166)

This reverts commit e1a36b53.

This reverts commit 1d600cee.

This reverts commit 0f7773ff.

This reverts commit 3df26ef1.

In particular the 'unsupported client version' error message
is now visible to the user when trying to connect to a
server that no longer supports the current client version.

NSIS installer module updates

Abort the request and reset the QNAM if user does not ACK a new cert.

The Processes plugin is no longer maintained, and OBS
compiles an up-to-date version of nsProcess for us.

This is supposed to fix bug #3283

Backport #3004 and #2978 to 1.8

Backport #3279 to 1.8