Feature request: #1512 Import doesn't do anything with no file name provided. 

Feature request: #1512 Import doesn't do anything with no file name provided.
https://sourceforge.net/p/phpmyadmin/feature-requests/1512/

Changes:
1) Mainly coding standards.
2) Fixed XHTML-compliant code "required" property.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>