downlaod), and the "check for file existence" option is enabled, then get the
file size as well and display that instead of the credit value. This fixes the
problem with files whose size has changed after they were uploaded or added
to the filebase. Directories which are not free still displayed with each
file's credit value (since that may not have any correlation with the file
size).
Display file sizes and credit values in a shorter more easy to read format
with suffixes for gigabytes (G), megabytes (M), kilobytes (K), and bytes (B).
Using an uppercase 'K' now to be more consistent with modern conventions
for abbreviating Kilobytes/Kibibyte (1024 bytes).