Fix #924 Not possible to create custom assertion with no arguments
Fix #924 Not possible to create custom assertion with no arguments

campbellwmorgan/nightwatch,nightwatchjs/nightwatch,nightwatchjs/nightwatch,beatfactor/nightwatch,joel-airspring/nightwatch,campbellwmorgan/nightwatch,Crunch-io/nightwatch,Crunch-io/nightwatch,joel-airspring/nightwatch