Modified README to include installation of Airflow

Author: abhiramr

Libraries_Tests/airflow/README.md

@@ -1,19 +1,24 @@
 ## Notes: 
 
+
+### Installation of Airflow:
+
+- pip install apache-airflow
+- pip install apache-airflow[all]
+
+### Initials:
+
 - Change path for DAGs in ~/airflow/airflow.cfg
-- Run airflow script using python <whatever-path>/<filename>.py
+- Run airflow script : python <whatever-path>/<filename>.py
 
 ### Commands to test and validate:
 
 - airflow list_dags
 - airflow list_tasks <dag_id>
 - airflow list_tasks <dag_id> --tree
-
 - airflow test <dag_id> <task_id> 2015-06-01
-
 - airflow backfill <dag_id> -s <start_date> -e <end_date>
 
 ### To run the local server:
 
-- airflow webserver
-
+- airflow webserver