fix path support for compiled-in libs on win32

Author: jmrohwer

pysces/__init__.py

@@ -64,7 +64,7 @@
 __SILENT_START__ = False
 
 extra_dll_dir = os.path.join(os.path.dirname(__file__), '.libs')
-if os.path.isdir(extra_dll_dir):
+if os.sys.platform=='win32' and os.path.isdir(extra_dll_dir):
     os.environ["PATH"] += os.pathsep + extra_dll_dir
 
 if os.sys.platform == 'win32':