New Rule Request

Statements should stand on their own line.

1. Why should this rule be added? Share links to existing discussion about what
   the community thinks about this.

   See header.

2. Provide several examples of what would and wouldn't trigger violations.

   let a = 1; let b = 2

3. Should the rule be configurable, if so what parameters should be configurable?

   Nothing to configure.

4. Should the rule be opt-in or enabled by default? Why?
   See README.md for guidelines on when to mark a rule as opt-in.

   Could be enabled by default as not too many violations are expected.