Added `api.check.is_conversation_view()` and `api.get.displayed_email_data()` for conversation view turned off.
Added `api.check.is_conversation_view()` and `api.get.displayed_email_data()` for conversation view turned off.

Added `api.tools.extract_email_address(str)` and `api.tools.extract_name(str)` for utility.

aneurycasado/gmail.js,mvnnn/gmail.js,esperco/gmail.js,liquidmetal/gmail.js,KartikTalwar/gmail.js,MaxMillion/gmail.js,avzabr/gmail.js,wakermahmud/gmail.js,kaushik94/gmail.js