Folding mechanism for while/for/if/switch-case

[jakub-suliga]

Problem:
Currently, there is no folding mechanism for while/for/if/switch-case statements in Eclipse. VSCode and IntelliJ support a folding mechanism for these statements. Therefore, I have created a method that implements this folding mechanism. This is also an open issue: #1426. In addition, I deleted some commented-out code from 2007.

Before:

After:

How to test:

1. Start an Eclipse workspace and create a new class.
2. Add while/for/if/switch-case statements to this class.
3. Verify that the folding mechanism works as expected.

Here is a small program you can use to test:
public class SimpleProgram {
   public void checkNumber(int number) {
       if (number > 0) {
           System.out.println(number + " ist positiv.");
       } else {
           System.out.println(number + " ist null.");
       }
   }

   public static void main(String[] args) {
       SimpleProgram program = new SimpleProgram();
       int count = 1;
       while (count <= 5) {
           System.out.println("Count ist: " + count);
           count++;
       }
   }
}

Bugs:

• [Bug] [Folding mechanism] Method declaration on the Same Line as the Closing Bracket #1539
• When there are multiple nested while/for/if/switch-case statements, not all foldable regions are recognized.

[iloveeclipse]

Please remove commented out code.