Integrate the book into the bundle docs

[dbu]

Go over the book and see what can be added to the respective bundle docs, remove the rest of the book.

Note: SimpleCmsBundle should no longer be mentioned, as its not maintained anymroe

http://symfony.com/doc/master/cmf/book/installation.html#acmemainbundle-and-simplecmsbundle
http://symfony.com/doc/master/cmf/book/installation.html#adding-new-pages
http://symfony.com/doc/master/cmf/book/simplecms.html