Remove unnecessary import.

Also remove unnecessary commen.
Merge pull request #45 from GraziaCiraulo/patch-3

Remove unnecessary import.
Remove dedicated applet target, add debug HTML file

All JAR targets will now sign the JAR file. Also, update the useless key.
Clean up the PDF manuals with the clean target
Honor debug compile-time setting
De-concretize configuration parameters handling

Add an interface (well, abstract class) for mechanisms that handle the
configuration parameters. This will allow to transparently implement an
in-memory store, that will be used when the java.prefs API is not available
or not desirable (e.g., in the applet or in unit tests).
In-memory ConfigStore implementation
Return in-memory ConfigStore if Prefs API is not available

Also: fix comments, add a method to get a temporary config store.
Use temporary config store in tests
Fix test HTML page and renew the useless key

Also, change the cname to EduMIPS64Team.
Use the error code as a message in SynchronousException
Add a method to set the global config object; use it in tests
Rename ConfigBuilder to ConfigManager
Make a CPU reset reload the ConfigStore object

This ugly hack is required to make the CPU see the changes made to the
ConfigManager, and especially useful during tests.

This is not the best way to solve this problem; something more explicit would
be better, but for the time being this will do.
Add JavaHelp JAR to libs, remove class files

The JavaHelp classes had been included as class files under libs. It looks
cleaner to me to include the JAR file in libs and, when creating the
standalone JAR, simply putting the class files inside the standalone JAR.
(Still, it's ugly. But less ugly.)
Fix potential null pointer exception
FindBugs found a potentially null pointer exception for the variable
read. 
This patch fixes it.