Reorganise the paragraphs in the rendering section a bit to allow easier reading.
Update the rendering section to support the positioning mechanism proposed
in https://www.w3.org/Bugs/Public/show_bug.cgi?id=20037#c15 for text positioning.
Adding overflow:hidden to cue background box.
Restore the .text attribute on VTTCue, since the attribute has
been removed on the parent interface, see
https://github.com/w3c/html/commit/580e7e6f98fbd82586aa7e894efbe8c16b99701f

Closes https://www.w3.org/Bugs/Public/show_bug.cgi?id=22905
Adding a static version of the spec, since respec is not reliable.
Also pointing to Overview.html now as the editor draft file.
Re-use common respec on source file - it got fixed.
Move to respec 3.2
Remove extraCSS.
Mark bug-assist as remove after spec creation.
Fix 2 typos found by respec 3.2.
Move local respec to 3.2.4 too.
Make "text position" actually define the position of the cue box as
discussed in https://www.w3.org/Bugs/Public/show_bug.cgi?id=20037 .
Remove surplus "computed text position anchor point".
Merge commit 'c84ec7734114195da3644fdac4793f311aee72fc' into revert-regions

Conflicts:
	webvtt.html
Merge commit '3d05e2e05c72b01404cf290bf07c7f0f367827a7' into revert-regions

Conflicts:
	webvtt.html
Partially revert "Update the rendering section to support the positioning mechanism proposed"

This reverts part of commit 3d05e2e05c72b01404cf290bf07c7f0f367827a7.

Conflicts:
	webvtt.html
Merge commit '7ce0d8ecddc193e18f8492de934e40839a538840' into revert-regions
Merge commit '797554b08f06cedae9e5568b3a91795492d9d395' into revert-regions

Conflicts:
	webvtt.html
Merge commit '8d5fe32cde8a99f5ae76545c5154fd8cca2975b7' into revert-regions

Conflicts:
	webvtt.html