Javadoc changes.

Removed imports to classes from top-level package which were just referenced by
{@link} tags.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/configuration/trunk@1554638 13f79535-47bb-0310-9956-ffa450edef68
[CONFIGURATION-562] Changed API of ExprLookup.

The class no longer supports setting an AbstractConfiguration object. Instead,
a ConfigurationInterpolator and a logger can be set. This change also removes a
cyclic dependency between the interpol and the top-level package.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/configuration/trunk@1554639 13f79535-47bb-0310-9956-ffa450edef68