[latexrefman] Small modification (or extension) to 28 Command line

[Pablo González L]

This is more a doubt/suggestion regarding this point, I think (it is my
personal opinion) that a more suitable title would be:

28 Command line interface

And I would add a small description of CLI implementing (I do not know
if it is POSIX or GNU) next move the text that is in 28.1 here

With many implementations you can specify command line options by
prefixing them with ‘-’ or ‘--’. This is the case for both TeX Live
(and MacTeX) and MiKTeX. We will use both conventions interchangeably.

Next to a note regarding the `=` sign that is mandatory for options
that take a value and should not have spaces before or after it.

As a novice, I put spaces and only got errors so the note :(