Issue #90 Choose which refactorings to apply on a Java file

TODO: sort out how the IRefactoring List is built.

ChooseRefactoringsWizardHandler.java, ChooseRefactoringWizard.java, ChooseRefactoringWizardPage.java: ADDED

plugin.xml:
Renamed commandId "org.autorefactor.ui.handler" to "org.autorefactor.automatic.refactoring".
Added commandId "org.autorefactor.choose.refactorings" for ChooseRefactoringsWizardHandler.

ApplyRefactoringsJob.java: ADDED - extracted from AutoRefactorHandler
Called by ChooseRefactoringWizard.

AutoRefactorHandler.java:
Made the code accessible to ChooseRefactoringsWizardHandler.

RefactoringsTest.java:
Now references
Fixed a NPE in ForLoopHelper.iterateOverContainer().