CMake: Update panda3d/__init__.py

- Python 2.7 EOL warning is now past tense
- Use os.add_dll_directory() when available (instead of hacking up PATH)

cmake/templates/win32_python/__init__.py

@@ -11,10 +11,13 @@ def _fixup_dlls():
     if not os.path.isdir(dll_path):
         return
 
-    os_path = os.environ.get('PATH', '')
-    os_path = os_path.split(os.pathsep) if os_path else []
-    os_path.insert(0, dll_path)
-    os.environ['PATH'] = os.pathsep.join(os_path)
+    if hasattr(os, 'add_dll_directory'):
+        os.add_dll_directory(dll_path)
+    else:
+        os_path = os.environ.get('PATH', '')
+        os_path = os_path.split(os.pathsep) if os_path else []
+        os_path.insert(0, dll_path)
+        os.environ['PATH'] = os.pathsep.join(os_path)
 
 _fixup_dlls()
 del _fixup_dlls

panda/CMakeLists.txt

@@ -122,7 +122,7 @@ if __debug__:
     import sys
     if sys.version_info < (3, 0):
         sys.stderr.write('''\\
-WARNING: Python 2.7 will reach EOL after December 31, 2019.
+WARNING: Python 2.7 has reached EOL as of January 1, 2020.
 To suppress this warning, upgrade to Python 3.
 ''')
         sys.stdout.flush()