Fix up how we print transfer string.
Fix up how we print transfer string.

First, document why the fixed string length is the
length that it is.  Second, truncate the filename
so that we preserve the end, not the beginning.  This
is likely to be most helpful, though it won't always
be.

Signed-off-by: Chris Lalancette <281cd07d7578d97c83271fbbf2faddb83ab3791c@irobot.com>

manuelnaranjo/git-got,jake4679/git-got