ciread: Print out index, as well as file offset

When printing many cache item entries together, it can be helpful to
see what index we're looking at, since we don't print is anywhere else
in the output. So, print it when we print the file offset.

Change-Id: I410b8ea14365a40620c55241a9cf5f7db0b869df
ciread: Adjust printf code formatting

Just move some code around when printing out an entry, to be clearer
about what we're doing and to make this easier to edit.

Change-Id: If47be3483fbc67016d6e4f41d40b0a78a834af4d
ciread: Print human-readable modtime

Along with the modtime in UNIX-epoch form, also print a human-readable
time, to more easily see when the modtime actually is.

Change-Id: Ifbe575fcc2c60eb36d39ab7f3a1594fe28a9caa2