Merge pull request #10 from updownlife/master

merging from master dec 04
modified sell.php to correct the following error:
When user inputs were incorrect, the form values is supposed to be retained for the inputs so the user don't have to enter them again. But the category field was getting reset to 'Books' instead of value chosen by user. Hence modified it.
Merge pull request #16 from ramyaps/master

modified sell.php to correct the following error: