Massive change @ComponentHolder class

Now component mapping/referencing method excludes components with no
given name
(no reference ready components) instead of throwing an inevitable null
pointer exception. Most of those excluded components are unwanted for
view management. Also the hashmap variable stored objects are now cast
as instances of JComponent class (previous Component).
JComponent is a base class for all Swing components, so a reference like
that prevents low level Component class instances from <<running>> into
mapComponent method.