adding start date to tasks

rowers/dataprep.py

@@ -40,8 +40,10 @@ from rowingdata import (
 )
 
 from rowers.metrics import axes,calc_trimp,rowingmetrics
+from rowers.models import strokedatafields
 
-allowedcolumns = [item[0] for item in rowingmetrics]
+#allowedcolumns = [item[0] for item in rowingmetrics]
+allowedcolumns = [key for key,value in strokedatafields.items()]
 
 from async_messages import messages as a_messages
 import os