[FS] Remove JNI based LocalFileHandler and its filesystem.win32 fragment

The new native Win32Handler is as fast as the JNI based implementation,
but simpler to maintain because it only uses JNA.
Therefore remove the more complex JNI based LocalFileHandler and the
o.e.core.filesystem.win32.x86_64 fragment that carries the compiled
native library.

Author: HannesWell