title: EXTjs: Sorting issue in extjs with number and string
body: <p>I have grid in extjs, where in column the value come as 200.00 GB, 12.00 GB, 23.34 GB. When i click on sorting it not shown in proper order like Ascending or decending. Please help me how to show the combination of number and string sorting. Check Image</p>
  
  <p><img src="https://i.stack.imgur.com/KR0Qj.png" alt="enter image description here"></p>