v0.2.30

• Fixes issue where the is-open class was not getting applied. This class will get added when the popover is triggered open, and removed once the popover has fully disappeared.
• Adds overflow: hidden to the main popover element, and overflow: visible when the popover's is-open class is added. This prevents the popover from taking up any space in the DOM when it is not open.
• The classes for previous positions will only be cleared when a new position has been determined - this fixes some weird visual bugs when opening/closing popovers frequently.