Add MemberThis rule. Rule explicitly adds 'this.' before local member…

[richardstanton]

… access.

Some projects use a different naming convention for member access. In an alternative convention in order to easily tell if a variable is a local member the "this." operator is always used. This convention takes a different approach from the existing PrivateFieldNaming rule that adds an underscore on members.

This change adds a MemberThis rule that is turned off by default. This would allow an alternative convention to be used by a project that wanted to use the codeformatter.

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[dnfclas]

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