Panic: assignment to entry in nil map

[flemeur]

Hi there!

First of all: Thank you for creating this awesome Go package! Until today I've had zero problems using it.

Unfortunately since the lastest release I've been getting panics from some of the requests made to the FB API. The code panics in addUsageInfo when res is nil. Maybe add a check for that case, like in addDebugInfo?

[huandu]

My fault. I'll fix it soon.

[flemeur]

Wauw, that was quick! Thanks! 😄