Edit Email template | Tags issues

Replication steps :
1.Login with Admin
2. Edit email template > Edit Template to End User
3. While tagging currently we have to enter "#"

Expected Result : Tags should be done by "@" as per requirement.
This change should be made generic, wherever tags are used in Edit templates
Refer DMS-34

cc - Priya Dhamande Hrishikesh Deshpande Samir Swapnil Pandhare