Introduce new single-page sample and toolbar configurators

[Piotrek Koszuliński]

The goal is to replace all the samples that we are currently shipping with the packages with short one that condenses the most important informations for someone who has just downloaded CKEditor package.

Additionally, we'll introduce new tools for toolbar configuration.

The old samples will be kept in the packages to not break all links and documentation that were created in past few years. However, they will not be exposed in the samples/index.html. The old index.html will be moved to index-old.html.