Added a LoggerContextFilter to accelerate the retrieval of the logger context when in JNDI environment
Added the LB license to some classes

ContextSelector implementations now also work as a registry. One can get a context based on its name, or get the names of all registered contexts.

Since it's a snapshot version and needs a special repository (snapshots.repository.codehaus.org), the repository info was added in the profile element.

Added direct <a name="" /> links in chapter 1 and 2

Several dependencies are declared with scope=compile and optional=true.
When a user application depends only on lb-classic, only the classic, core and slf4j-api are packaged. Any other dependency
has to be managed by the user: logback does not include any other jars by itself.

Split of the short intro into a chapter1: introduction and chapter2: architecture. Moved examples accordingly