Changed char limit of goal title from 20 to 100

Feedback from @Lobacrow: I think goals should serve the goal setter first and foremost. 20 characters is pretty stringent. I'm not saying no limit, I just think that one is quite low. Now I'm wasting time figuring out how to name my goal in 20 characters instead of writing about it.

Jason: I like your point that the goals should serve the user. Though we gotta draw the line somewhere though, so it will never be 'enough' to suit everyone's preferences, so to speak. (Reminds me of the twitter char limit debate) When I set it to 20, i was coming from the perspective of wanting to keep things less cluttered and easier to scan, for a cleaner visual exp for everyone.

But separately I already truncate the text in the goal tags, so that serves the objective already. Longer goal titles in the profile page looks acceptable. So yeah, don't see why I need that low char limit now. Will raise it to 100 then - should be more than enough. Fits all the longer goal titles we have right now.