Update contents and style of the manual.

This change:

* Adds much more info for beginners - section 1 (introduction to your train), section 2 (train driving basics), section 3 (standard operations) and section 6 (glossary) are mostly new content. Sections 4 and 5 are mostly untouched (but could do with more info, diagrams, etc.)
* Updates the style and generally prettifies it.
* Uses very clean HTML5 so that @Donkie's pagination script should be easier to implement.

What's still to be done:

* Railway signs: @PhoenixBlack explains these in [http://foxworks.wireos.com/metrostroi/manual3.html](http://foxworks.wireos.com/metrostroi/manual3.html). There are also some Russian-language signs that appear in http://brain.wireos.com/pub/metro/isi.pdf (6.17, 6.19, 6.20, 6.22)
* Technical diagrams showing a mid-level overview of the electric and hydraulic systems.