#1423 New rule SingleMethodSingleton Documentation

[Rei Angelus]

Hello,

The SingleMethodSingleton rule is called SingleMethodRule and refer to rulesets/java/design.xml/SingleMethodSingletonRule in the changelog. It doesn't seem to be correct.

Moreover, in the online documentation, the rule description is the same as SingletonClassReturningNewInstance. It seems like a copy/paste error.

Thanks,