not to cache each objects; so hard to make things work.
a class for constructing an object.
use Forge class to generate an object.
use apc as cache for dependency information.
removed unused class; taken over by Forge class.
fixed PHPDoc to use Forge, renamed some variables/methods for clarity.
added test for option.
added option to override the dependencies when constructing an object.
fixed a bug...
easy to turn on/off useApc...
not to use getInstance; just use new.