Document x86 and ARM with annotations and references

Squashed commit of the following:

commit 05689e26e9acee95776149914c9d6eb05ce32a08
Author: Piotr Czarnecki <pioczarn@gmail.com>
Date:   Sat Jan 18 16:01:01 2014 +0100

    Fix readme

commit 9258302d711e96d8b66a7b541cffbc5e59a4ede4
Author: Piotr Czarnecki <pioczarn@gmail.com>
Date:   Sat Jan 18 15:16:07 2014 +0100

    Fix README.md, add x86 Readme

commit e072f2a03794fab35bf298870d9f4f76cb5a99f0
Author: Piotr Czarnecki <pioczarn@gmail.com>
Date:   Sat Jan 18 15:14:20 2014 +0100

    ARM: annotations and README.md

commit 3e60a65df92117edcb0dc2cd1be795b49089a108
Author: Piotr Czarnecki <pioczarn@gmail.com>
Date:   Sat Jan 18 14:25:10 2014 +0100

    x86: start annotating code