A variety of docbook dcoumentation corrections and style fixes

[grimreaper (Eitan Adler)]

This makes a number of changes

• changes "the the" the "the
• changes "that that" to "that"
• moves closing </para> tags around <itemlists> to where they belong
• adds commas after "i.e." and "e.g." (since this was inconsistent prior)
• removes duplicate words such as "file" after <file> and "command" after <command>
• avoids using "e.g.," where plain english is better
• avoids using "you" or "your" where possible
• avoids "invoke" where "run" is better
• capitalizes titles

and misc other changes

I apologize for making this one large diff

[grimreaper (Eitan Adler)]

a collection of docbook fixes

[grimreaper (Eitan Adler)]

updated ticket to fix additional issues:

• all listitems must have <para> as their immediate child
• filename must not have emphasis (but replaceable is okay)

[larryv (Lawrence Velázquez)]

I'll try to work through this soon, if Mihai doesn't get around to it.

[Ionic (Mihai Moldovan)]

And he spoke: 'Have mercy on your Developer, for tasks are plentiful, but time meager.'

-- Ionic 4:2

[larryv (Lawrence Velázquez)]

If you get to this before I do, I'd suggest breaking it up into separate commits for spelling/grammar mistakes, missing punctuation, markup errors, etc. (granularity at your discretion).

[Ionic (Mihai Moldovan)]

• capitalization in r134581
• grammar related to e.g. and i.e. in r134582 (+ replacing i.e. with e.g. where appropriate)
• removed redundant wording for stuff already wrapped up in markup like <command> in r134583
• deduplicated words words in r134584
• <para> tag fixes in r134585
• <emphasis> to <replaceable> in r134586
• indentation and whitespaces in r134587 (+ a lot of other stuff that was not included in the original submitted diff)
• OSX to OS X in r134588 (not part of this diff.)