Fix inline comments syntax

[DrewAPicture]

Just need a catch-all place to corral commits for inline comments syntax fixes. This will mostly be things like fixing casing and full-stops on single-line comments, and multi-line comment styles.

See: ​http://make.wordpress.org/core/handbook/inline-documentation-standards/php-documentation-standards/#5-inline-comments

[DrewAPicture]

In 29205:

Fix syntax for single- and multi-line comments in root-directory files.

See #28931.

[DrewAPicture]

In 29206:

Fix syntax for single- and multi-line comments in wp-admin-directory files.

See #28931.

[DrewAPicture]

In 29229:

Fix syntax for single- and multi-line comments in wp-includes/class-http.php.

See #28943 and #28931.

[DrewAPicture]

Let's call this fixed and pick it up again in tickets targeted at specific files or functionality.