Adding a logging utility for improved logs

ml-agents/mlagents/logging_util.py

+import logging
+
+
+def create_logger(name):
+    log_level = logging.INFO
+    log_format = "%(asctime)s %(levelname)s [%(filename)s:%(lineno)d] %(message)s"
+    logging.basicConfig(level=log_level, format=log_format, datefmt="%Y-%m-%d %H:%M:%S")
+    logger = logging.getLogger(name=name)
+    return logger
+
+
+# TODO
+"""
+1. change mlagents.trainers to mlagents_trainers
+2. logger should be in lowercase in all files
+3. if logger is not used in a file then it should be deleted
+"""