v2.1.0

• [#2839] Added support for theming via theme prop. Thanks akx
• [#2874] Fixed flow-types of MultiValue components. Thanks mike1808
• [#2903] Fix missing form input when there isn't a selected value. Thanks alvinsj
• [#2934] Reduced theme colors to a sane value set to make the exported theme more easy to consume and configure. Thanks jossmac
• [#2876] Added overflow hidden to valueContainer to stop overflowing text in the control. Thanks mike1808
• [#2975] Separated menu placement logic from menu primitive. Thanks jossmac.