Bug fix: Some products installing with .tmp appended to their folder name.
Bug fix: 'Invalid data' error when trying to upgrade plugin.
Silencing deprecated notice: get_themes is deprecated since version 3.4! Use wp_get_themes() instead.
Product ID becomes package ID
Remove upgrade functionality from single product page.
Rename all the  variables to .
Remove the package ID from the nonce so it can be used to install any package.