Support jsdoc @throws

[djolejov]

First of all, awesome extension idea! Really looking forward to it gaining popularity and support!
My suggestion would be to also look for @throws, and marking "Function call that may throw" accordingly. Maybe adding a different setting for functions that have @throws, so the severity can be different for them, when marked "Function that may throw".
With this, analysis wouldn't have to be as deep. (Or perhaps it can even stay one level deep as it is now)