Lesson 2 - Explaining arguments/flags more clearly

[SarahKateSchafer]

This refers to Lesson 2 in the Unix Shell - https://librarycarpentry.org/lc-shell/02-navigating-the-filesystem.html

When arguments/flags are first mentioned in Lesson 2, their function could be made clearer.
For example, an explanation that with command ls:
-l is for outputting as a long list;
-h is for outputting in human-readable form; and
-S is for sorting (largest first).

These are covered in more detail later, but when they first appear, it is quite cryptic!

[alex-ball]

It would be great if you could suggest ways of working these explanations into the lesson text.

Here are the relevant parts for comparison:

lc-shell/_episodes/02-navigating-the-filesystem.md

Lines 59 to 61 in 0366d2d

	If we type `ls -l` and hit enter, the computer returns a list of files that contains
	information similar to what we would find in our Finder (Mac) or Explorer (Windows):
	the size of the files in bytes, the date it was created or last modified, and the file name.

lc-shell/_episodes/02-navigating-the-filesystem.md

Lines 81 to 83 in 0366d2d

	Luckily, there's another flag `-h` that when used with the -l option, use unit suffixes:
	Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the
	number of digits to three or less using base 2 for sizes.

(The grammar in the above extract could do with some attention, and what it says is not what it means.)

lc-shell/_episodes/02-navigating-the-filesystem.md

Lines 248 to 255 in 0366d2d

	> > To order files in a directory by their filesize, in combination with the `-l` argument:
	> >
	> > ~~~
	> > ls -lS
	> > ~~~
	> > {: .bash}
	> >
	> > Note that the `S` is **case-sensitive!**