Adds a wizard step to this path. Paths must contain at least one step, and the steps
will be traversed in the order they are added.
Parameters: step - the next WizardStep in the path.
Checks if the specified step is the first step in the path.
Parameters: step - the step to check true if the step is the first in the path, false otherwise.
Checks if the specified step is the last step in the path.
Parameters: step - the step to check true if the step is the last in the path, false otherwise.