Msf::Module method specs

MSP-11496

Use respond_to matcher to check that methods aren't dropped during
reorganization.
Spec Msf::Module::Failure

MSP-11496
Spec Msf::Module::UpdateableOptions

MSP-11496
Spec Msf::Author

MSP-11496
Spec Msf::Reference

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Spec Msf::SiteReference

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Spec Msf::Platform

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Spec Msf::Target

MSP-11496
Merge branch 'land/4028' into upstream-master

Land #4028