Align assorted trac things

[samuelsidler]

ALIGN ALL THE THINGS, is the end goal here.

The attached patch aligns the trac navigation and content area with the left edge of "Showcase". This is consistent with what we do throughout the site.

This patch does *not* align the h2 with Showcase.

(I also removed a weird border rule that isn't actually used.)

[samuelsidler]

Here's a before and after shot: ​http://cl.ly/image/3D2o1n0S1D3p

[nacin]

In 77:

Trac styles: Align the left edges. props samuelsidler. fixes #167.

[nacin]

I also had a local change for resetting the background for #headline h2 that I lumped into [77].

[SergeyBiryukov]

[77] brought back the issue with reports width (see ​comment 32 on #wp24165).

meta-167.2.diff​ restores full width for reports and replaces 960px references with 940px, which I guess was the intent of 167.diff​.

[nacin]

In 78:

Trac styles: Fix report width, broken in [77]. props SergeyBiryukov. fixes #167.

[nacin]

In 79:

Trac styles: Fix overeager rule added in [77]. See #167.

[samuelsidler]

The change in meta-167.2.diff​ misaligns the trac nav. meta-167.3.diff​ fixes that.

(Aside: I really dislike how pixel perfect everything is. One day, we should rewrite it to be a bit more flexible but still aligned properly.)