Grunt task does not stop on validation error

[olegjs]

Running "validation:dist" (validation) task                                                                                                                                          
Validation started for.. src/index.html                                                                                                                                              
1=> "An a start tag seen but an element of the same type was already open." Line no: 321                                                                                             
2=> "Stray end tag a." Line no: 324                                                                                                                                                  
No of errors: 2                                                                                                                                                                      

Running "htmlmin:dist" (htmlmin) task                                                                                                                                                
File dist/index.html created.                                                                                                                                                        

Running "cssmin:dist" (cssmin) task                                                                                                                                                  
File dist/main.css created.    

[cvrebert]

X-Ref: #2.

[cvrebert]

Have submitted #22 to fix this.