[hack] Add special comment types to schema
[hack] Add special comment types to schema

Summary:
I've added special comment types for fixme, unsafe, etc, comments to the schema.

No lexing of them yet. I just wanted to get the gear in place first.

The formatters should deal with them the same way they deal with single line or delimited comments, respectively.

Reviewed By: jamesjwu

Differential Revision: D4364660

fbshipit-source-id: fa973e31b879db46b6d7594048d64e4fa79b4785

jamesgpearce/flow,samwgoldman/flow,jamesgpearce/flow,mroch/flow,mroch/flow,nmote/flow,nmote/flow,mroch/flow,facebook/flow,facebook/flow,mroch/flow,TiddoLangerak/flow,gabelevi/flow,jamesgpearce/flow,fletcherw/flow,nmote/flow,gabelevi/flow,facebook/flow,ForbesLindesay/flow,ylu1317/flow,JonathanUsername/flow,fletcherw/flow,jamesgpearce/flow,JonathanUsername/flow,JonathanUsername/flow,popham/flow,gabro/flow,MichaelDeBoey/flow,claudiopro/flow,ForbesLindesay/flow,jamesgpearce/flow,popham/flow,popham/flow,TiddoLangerak/flow,popham/flow,gabro/flow,nmote/flow,AgentME/flow,facebook/flow,facebook/flow,ylu1317/flow,ForbesLindesay/flow,ForbesLindesay/flow,facebook/flow,samwgoldman/flow,gabelevi/flow,JonathanUsername/flow,ylu1317/flow,TiddoLangerak/flow,ForbesLindesay/flow,gabro/flow,AgentME/flow,TiddoLangerak/flow,mroch/flow,ylu1317/flow,claudiopro/flow,gabro/flow,fletcherw/flow,JonathanUsername/flow,mroch/flow,samwgoldman/flow,popham/flow,nmote/flow,AgentME/flow,mroch/flow,TiddoLangerak/flow,claudiopro/flow,samwgoldman/flow,JonathanUsername/flow,ForbesLindesay/flow,claudiopro/flow,nmote/flow,AgentME/flow,fletcherw/flow,nmote/flow,MichaelDeBoey/flow,gabelevi/flow,jamesgpearce/flow,samwgoldman/flow,jamesgpearce/flow,AgentME/flow,fletcherw/flow,gabro/flow,ylu1317/flow,MichaelDeBoey/flow,claudiopro/flow,gabelevi/flow,popham/flow,JonathanUsername/flow,gabro/flow,samwgoldman/flow,fletcherw/flow,popham/flow,gabelevi/flow,facebook/flow,MichaelDeBoey/flow,samwgoldman/flow,gabelevi/flow,MichaelDeBoey/flow