move static numpy functions to another header

- use env variables
- change warnings back to ON

python/example/read_frame.py

@@ -1,7 +1,13 @@
+import os
+from pathlib import Path
 from aare import File, Frame
 
 if __name__ == "__main__":
-    file = File("/home/bb/github/aare/data/jungfrau_single_master_0.json")
+    #get env variable
+    root_dir = Path(os.environ.get("PROJECT_ROOT_DIR"))
+    data_path = str(root_dir / "data"/"jungfrau_single_master_0.json")
+
+    file = File(data_path)
     frame = file.get_frame(0)
     print(frame.rows, frame.cols)
     print(frame.get(0,0))