Enable JSHint `eqnull` option
Enable JSHint `eqnull` option

Fixes gh-149

yeoman/generator-node,canercandan/generator-node,zckrs/generator-node,rhettl/generator-node,thehobbit85/generator-node,stevemao/generator-node,davewasmer/generator-node,iamstarkov/generator-node,RobertJGabriel/generator-node