Design API: refactoring, new KibaOneAccents class

[ Feature description ]

KibaOneAccent is a static class with which provides helper methods
to get accents information.

* KibaOneAccents::WHITE

  The color to use as white

* KibaOneAccents::BLACK

  The color to use as black

* KibaOneAccents::getAccents()

  Returns an array of all available accents.

  Each item is an array of 3 values:
    - the accent name
    - the accent color
    - the headings color (appliable for footer headings)

* KibaOneAccents::exists ($accentName)

  Determines if an accent exists

* KibaOneAccents::getAccentColor ($accentName)

  Gets the accent color of the specified accent

* KibaOneAccents::getHeadingColor ($accentName)

  Gets the headings color of  the specified accent

[ Public API code change ]

The API code nows use the KibaOneAccents::getAccents() method.

[ Goal ]

To allow the use by our header/footer API of the accents information.
Design API: adding /design//header

Returns an header to add to a Wolfplex web document

[ Specifications ]
http://www.wolfplex.org/w/index.php?title=API&oldid=1723#.2Fdesign.2Fheader

By addition to these specifications, html5 is considered as a valid
value for the framework.