[hack] Revisit escaping strings in default values
[hack] Revisit escaping strings in default values

Summary: This diff revisits escaping strings in default values and corrects some things we have missed like non printable chars

Reviewed By: aaronkroth

Differential Revision: D6679124

fbshipit-source-id: fb959885d654937e8ac1d6c4c06927e4f8ce6985

samwgoldman/flow,facebook/flow,popham/flow,JonathanUsername/flow,claudiopro/flow,AgentME/flow,samwgoldman/flow,gabelevi/flow,nmote/flow,samwgoldman/flow,claudiopro/flow,jamesgpearce/flow,JonathanUsername/flow,samwgoldman/flow,nmote/flow,samwgoldman/flow,facebook/flow,jamesgpearce/flow,gabelevi/flow,JonathanUsername/flow,mroch/flow,nmote/flow,facebook/flow,gabelevi/flow,JonathanUsername/flow,gabelevi/flow,nmote/flow,JonathanUsername/flow,popham/flow,jamesgpearce/flow,AgentME/flow,gabelevi/flow,JonathanUsername/flow,nmote/flow,mroch/flow,mroch/flow,popham/flow,AgentME/flow,jamesgpearce/flow,gabelevi/flow,nmote/flow,claudiopro/flow,nmote/flow,mroch/flow,AgentME/flow,claudiopro/flow,facebook/flow,JonathanUsername/flow,popham/flow,facebook/flow,facebook/flow,jamesgpearce/flow,popham/flow,facebook/flow,claudiopro/flow,gabelevi/flow,popham/flow,jamesgpearce/flow,mroch/flow,popham/flow,samwgoldman/flow,jamesgpearce/flow,mroch/flow,AgentME/flow,samwgoldman/flow,mroch/flow