Make need for time setting more obvious

[adampbeardsley]

At our workshop we mentioned a couple times that we need to set the time before taking data. But people are absorbing a lot, so it got overlooked. The people at the ARRL workshop also missed it.
So somehow we need to make it more obvious / harder to miss the need to set the time.

[NHeier]

here's a solution I worked out.

• if started without internet it will show this error when start is pressed
• if at any point it connects to internet the error will not show
• if the user sets the time, the error will not show.
• the user can ignore future warnings by hitting ok. (maybe they reloaded the GUI)