Add exit confirmation on KEY_START

[ckohnke]

Added some very basic exit logic to print a confirmation message on KEY_START event. The segment loops while waiting for a key press and then exit (KEY_B), save&exit(KEY_R), or cancel (KEY_L) the exit procedure based on the response. Crude, but works as a first pass at the feature. A lot of data went untransfered today by accident, so I decided to add this in.

First commit is using expanded tabs instead of hard tabs. The second commit replaces the expanded tabs with hard tabs. Tabs vs. spaces are going to be the death of me...

My C++ is insanely rusty, but I hope to help contribute more in the future.

[gocario]

Thank you for your contribution. Unfortunaly, your pattern doesn't really match with my pattern. I made a quick class to exit with saving prompt. Maybe there is more file, more code. But I feel it better. Thanks again.

PS: Tabs > Spaces