Execute custom command on document option

[usrflo]

Please add a menu item to execute a custom command on a document: e.g. this can be used to attach a document to a new email, execute a special archiving script or any other post-processing.

Sample command to create a new email with Thunderbird plus attachment:
thunderbird -compose "attachment='$1'"

BTW: in evince this feature is available by the "Send to ..." menu item.