PATH out the deps to metasploit-concern and metasploit-model, for the moment
Also PATH out the deps for metasploit-credential and metasploit_data_models

MSP-11412
Specific require all metasploit gem dependencies' engines

MSP-11412
Ensure require of metasploit/credential/engine is optional
Bump metasploit gem dependencies

MSP-11412
Use the prerelease versions of the gems

MSP-11412
Bump to newly-released versions of gems

MSP-11412
Optionally require mdm, as well

MSP-11412
Rename the method for optional requires

MSP-11412
Lands #3943, changes to engine require