Use ManagedLgIcuCollator on Windows (FWNX-296)

It improves maintainability if we use the same implementation
on Linux and Windows, therefore we use the ManagedLgIcuCollator
on Windows as well and remove the unmanaged implementation of
LgIcuCollator.
(cherry picked from commit cee1fbd501dbcce48be433a42a43aa91d57051bf on
develop)

Conflicts:
	Build/FwBuildTasks.dll

Change-Id: I2de8604078818c5c8555ba4ae0a3a01b75344fb0