Add Travel Costs / Travel Hours and milage (KM) fee

[kayvanaarssen]

Would be a nice feature to add Travel Costs / Travel Hours.
We often need to drive to clients and some have a fixed price. But others have Travel Hours / Waiting Hours (in Maritime Work)
So those are calculated on a different hourly rate.

Also adding driven miles / kilometers would be a nice add-on if they are billed seperate or just for bookkeeping records (needed with company cars). Could choose to enter manually or Office Location <> Client Location and calculate based on maps.

Sorry also just found: #897

But really think this would be an amazing feature for Solidtime. Many time tracking tools are missing this - and its for us at least a missing thing in Toggl for example that we now use. So the registration it NOT complete and thus we still need to do things in Sheets / other programs and things will get lost / forgotten and not invoiced.