Remove trailing whitespace.
Code style adherence.

* Spaces to tabs.
* Whitespace inside parentheses etc.
* Insertion and removal of empty lines for spacing.
* Comment reflow.
* Remove a few redundant code blocks.
Style, wording, and typography fixes.

* Dot and parentheses on function names.
* Better header style when only function names.
* Inline code markup on more words.
* Always link internal links with trailing slash.
* Various small style adherence fixes.