FIX: Properly capitalize unit letters

* Revert commit b19d276 but keep the last 'K' for kibibyte uppercased

The symbol 'k' indicates the decimal unit prefix 'kilo-' and must be written
in lowercased form; and the unit 'bit' would usually be written in lowercase
'b' to avoid confusing with 'B' for 'byte'.

* Add comments about different units

Author: Low-power

dool

@@ -1924,12 +1924,15 @@ def cprint(var, ctype = 'f', width = 4, scale = 1000):
             return theme['error'] + '-'.rjust(width) + theme['default']
 
     if base != 1024:
-        units = (char['space'], 'K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
+        # Miscellaneous value using base of 1000 (1, kilo-, mega-, giga-, ...)
+        units = (char['space'], 'k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
     elif op.bits and ctype in ('b', ):
-        units = ('B', 'K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
+        # Bit value using base of 1000 (bit, kilobit, megabit, gigabit, ...)
+        units = ('b', 'k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
         base = scale = 1000
         var = var * 8.0
     else:
+        # Byte value using base of 1024 (byte, kibibyte, mebibyte, gibibyte, ...)
         units = ('B', 'K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
 
     if step == op.delay: