Make character limit 200 on name and slug fields.

The following maxes out all the checks that existed on input forms from 20 to 200 (the character limit for wp_term name and slug is varchar(200)). While the maxlength of the input field was at 20, there were a number of checks for length 50 (ex: When editing an editorial metadata's name, if you maxed it out to 50 characters it would fail). I don't know if there was a reason for that. Maybe it should be capped at 50 instead of 20?