Log view diff line

[Jerry Nairn]

Suggested changes to diff links in the log view:

On the four lines which have:

$diff = ''; $printed = 1;

I have changed it to:

$diff = ','; $printed = 1;

I feel it is clearer with the separator in it. Other characters or
combinations of characters might be better.

I changed the string ' next main ' to ' to next main ' to be
consistent with the other links, ' to previous ' and ' to branchpoint
'.

Thanks,

Jerry Nairn