Updated LineHandler to use new handler base class
Updated LineHandler to use new handler base class

tsotetsi/textily-web,pulilab/rapidpro,pulilab/rapidpro,tsotetsi/textily-web,tsotetsi/textily-web,pulilab/rapidpro,pulilab/rapidpro,tsotetsi/textily-web,tsotetsi/textily-web,pulilab/rapidpro