Mark time entries as "billed"

Until now you were able to mark time entries as "billable" or not billable. In order to facilitate your invoicing, we have improved this function:
Now you can mark billable times as "already billed". Via the reports page, you are able to filter or group your time entries by billability. In this way you are able to find not yet billed revenues.
The first example image on the left shows how you can mark a whole group of time entries as already billed. The second one shows the filter function on the reports page.
