Add parens to mixins to avoid including in .css
Add parens to mixins to avoid including in .css

Auditors: emily

JetStarBlues/KaTeX,frankandrobot/KaTeX,franciscop/KaTeX,azotova/KaTeX,franciscop/KaTeX,mcanthony/KaTeX,crepererum/KaTeX,twitwi/KaTeX,twitwi/KaTeX,Khan/KaTeX,JetStarBlues/KaTeX,gagern/KaTeX,mcanthony/KaTeX,twitwi/KaTeX,zhanghuiguoanlige/KaTeX,xymostech/KaTeX,saschatimme/KaTeX,crepererum/KaTeX,zhanghuiguoanlige/KaTeX,frankandrobot/KaTeX,crepererum/KaTeX,saschatimme/KaTeX,kwangkim/katex-npm-0.7.0-pre,azotova/KaTeX,zhanghuiguoanlige/KaTeX,franciscop/KaTeX,xymostech/KaTeX,JetStarBlues/KaTeX,kevinbarabash/KaTeX,mcanthony/KaTeX,kevinbarabash/KaTeX,zhanghuiguoanlige/KaTeX,xymostech/KaTeX,zhanghuiguoanlige/KaTeX,crepererum/KaTeX,spicyj/KaTeX,gagern/KaTeX,frankandrobot/KaTeX,xymostech/KaTeX,twitwi/KaTeX,saschatimme/KaTeX,kwangkim/KaTeX,JetStarBlues/KaTeX,kwangkim/katex-npm-0.7.0-pre,franciscop/KaTeX,kwangkim/KaTeX,kwangkim/KaTeX,mcanthony/KaTeX,saschatimme/KaTeX,Khan/KaTeX,franciscop/KaTeX,kwangkim/KaTeX,spicyj/KaTeX,spicyj/KaTeX,spicyj/KaTeX,azotova/KaTeX,mcanthony/KaTeX,kevinbarabash/KaTeX,azotova/KaTeX,JetStarBlues/KaTeX,saschatimme/KaTeX,kwangkim/katex-npm-0.7.0-pre,spicyj/KaTeX,Khan/KaTeX,kwangkim/katex-npm-0.7.0-pre,xymostech/KaTeX,twitwi/KaTeX,gagern/KaTeX,gagern/KaTeX,gagern/KaTeX,kevinbarabash/KaTeX,kevinbarabash/KaTeX,frankandrobot/KaTeX,azotova/KaTeX,kwangkim/KaTeX,kwangkim/katex-npm-0.7.0-pre,frankandrobot/KaTeX,crepererum/KaTeX