fdo#86745 - Possible exception/segfault in jurt jpipe.dll under Windows ...

- Remove the LoadLibrary from DLLMain (from windows not recommended)
   see http://msdn.microsoft.com/en-us/library/windows/desktop/ms682583(v=vs.85).aspx
   in section Remarks
- Improve the comment why we need two dll's (jpipe.dll and jpipx.dll)
- Integrate CriticalSection, init in DllMain see link
   http://msdn.microsoft.com/en-us/library/windows/desktop/dn633971(v=vs.85).aspx#general_best_practices

Signed-off-by: Stephan Bergmann <sbergman@redhat.com>: removed the unsafe module
== NULL check around the critical section in getFunction

Change-Id: I6d5f655a4942437f6dc722236f6c371063e2c407