Stupid-Table-Plugin: Don't sort a column with same values

for a column whom all its values are the same, do not bother sorting. Touching the DOM for no reason costs in performance and if better to avoid.

Here’s a quick idea how to check if all columns values are the same:

var table = document.querySelector('table'),
    rowsCount = table.rows.length,
    values = {};


// lets say a user is sorting the first column
// skip the first tr which only has "th"..
while( rowsCount-- > 1){
  values[ table.rows[rowsCount].children[0].textContent ] = 1;
}

// same value if the object has less than 2 keys
if( Object.keys(values).length < 2 )
   return; // do not sort