This uses Codex provided colors in AbuseFilter primarily to
make it compatible some parts such as the log table with
the dark mode.
This however doesn't touch Ace highlight customisation of
the extension as Ace itself isn't dark mode compatible yet
the far I know.
It treats one #aaa color for borders the same as #a2a9b1
and uses a darker text color for deleted vs disabled
unlike what was before as I tried to both make it distinguishable
but use @color-disabled for that disabled style.
Change-Id: Ifddbda378754260ca8d8802bfd8c6c98de8e1def