Redesign index.php & Remove newblue-style & Bugfixing

Bugfixing:
- account.php: out-comment the bitfield per peer settings
- details.fun.php: bitfield-image no longer needed

Redesign index.php:
- index.php: added a new div "contentcontainer" to surround "sidebar", "content" and "rightbar".
- style.css: modified the css settings to adjust the content-div in the right behavior
  --> with sidebar/rightbar => Three column liquid layout
  --> without sidebar/rightbar => use 99% of the available space

Remove newblue-style:
- newblue-css-layout is no longer supported