Fix RCS1211

[jamesHargreaves12]

When removing unnecessary else blocks we need to also check if it conflicts with any other switch blocks (If the else is located at the top level of a switch selection).
e.g. in the following example, we cannot apply RCS1211 to remove the else.

        switch(i)
        {
            case 0:
                if(flag)
                {
                    var z = 1;
                    return z;
                }   
                break;
            case 1:
                if(flag)
                {
                    var y = 1;
                    return y;
                }
                else
                {
                    var z = 1;
                    return z;
                }
        }

The logic here is identical to removing the braces around the switch statements and so I just refactored that method out into its own helper class.

[josefpihrt]

@jamesHargreaves12 sorry the late review.