Release 0.0.31

• Merge pull request #116 from 8845musign/improve-children-prop (52b8184)
• Box may be specified without children in as prop (1ef59ec)
• Merge pull request #115 from 8845musign/chenge-style-field (f7c339b)
• improve children prop (6e949fa)
• fix format (58b8e52)
• delete disabled (2a44901)
• apply new style (e6d5da7)
• Merge pull request #114 from 8845musign/add-wrap-to-inputgroup-component (b9eea18)
• When laying out checkboxes, etc. horizontally, enable wrapping to prevent layout breakdowns. (8203cfe)
• fix typo (25e9cb0)