Search Atom packages.

multiline-bracket

Split the contents within brackets/braces over multiple lines
bhml
343

smart-tags

Prevent double input of brackest, curly braces, and quotes as in sublime text
pudymody
2,785

prismatic-parens

Prismatic Parentheses makes all your parens, braces, and brackets beautiful
calebmeyer
395

bracket-padder

Convenient padding and closing of brackets.
viablelab
2,503