ADD: ds (disksize) base-structure
ADD: invalid argument
ADD: error - line break
UPD: help, version, function names
ADD: get device size, check for root-user, get and calculate the right unit
UPD: ds(disksize) -> di (diskinfo)
ADD: blockcount, blocksize
ADD: new/bigger units (peta, exe, zetta, yotta)
UPD: title
UPD: factor (help)
ADD: showList - all devices