Resize log view columns on startup, to fit the optimal size of contents

[tibirna]

Today’s behavior, that makes the description column not wide enough and the author or date column way too large, is harmful for usability.

Compute the minimum/optimal size of contents and resize automatically. If this optimal sizing is changed by the user manually, record it and restaure it at restart.

Q: save by repository?

[mwoehlke]

Q: save by repository?

Yes, please. Saving the column widths shouldn't be too hard, is probably TRTTD, and mitigates the need to guess.