Fix alignment for file sizes

[jmks]

Description

File size can be up to 1023 B/KiB/etc.
The simplest solution is to allow 4 characters for alignment.

Before:

  rw-r--r--  somebody  staff  143 KiB  Sat Oct 13 14:27:58 2018    Visual_SQL_JOINS_orig.jpg
  rw-r--r--  somebody  staff  1021 B    Sat Oct 13 14:29:01 2018    a-file
  rw-r--r--  somebody  staff    0 B    Tue Nov  7 02:02:07 2017    a.md
  rw-r--r--  somebody  staff    0 B    Tue Nov  7 02:02:03 2017    a.txt
  rwxr-xr-x  somebody  staff  170 B    Tue Nov  7 02:02:02 2017    symlinks/
  rw-r--r--  somebody  staff  447 B    Tue Nov  7 02:02:04 2017    z-file
  rw-r--r--  somebody  staff    0 B    Tue Nov  7 02:02:06 2017    z.txt

After:

  rw-r--r--  somebody  staff   143 KiB   Sat Oct 13 14:27:58 2018    Visual_SQL_JOINS_orig.jpg
  rw-r--r--  somebody  staff  1021 B     Sat Oct 13 14:29:01 2018    a-file
  rw-r--r--  somebody  staff     0 B     Tue Nov  7 02:02:07 2017    a.md
  rw-r--r--  somebody  staff     0 B     Tue Nov  7 02:02:03 2017    a.txt
  rwxr-xr-x  somebody  staff   170 B     Tue Nov  7 02:02:02 2017    symlinks/
  rw-r--r--  somebody  staff   447 B     Tue Nov  7 02:02:04 2017    z-file
  rw-r--r--  somebody  staff     0 B     Tue Nov  7 02:02:06 2017    z.txt

Note that the digits for the size of a-file is now properly aligned.

• Relevant Issues : "colorls -l" -- incorrect alignment when file size < 1KiB #190
• Relevant PRs : (none)
• Type of change :
  • New feature
  • Bug fix for existing feature
  • Code quality improvement
  • Addition or Improvement of tests
  • Addition or Improvement of documentation

[avdv]

Thank you @jmks!