R1:77ababadcb78

Update Legalpad for handleRequest

Summary: Updates Legalpad for handleRequest instead of processRequest

Test Plan: New Document, Sign Document, Add exemption, view signatures.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D13756