Better handling of content-length limits in workspace fields

[sei-jbooz]

Some workspace fields have a character limit that is not surfaced in the UI. The current behavior is for the TM API to throw an exception (from the database) when a user tries to save data that is too long. The UI is never notified of this, so the changes just silently fail to save.

The UI should be better about communicating character limits and preventing users from typing in too much data.