PSEXEC Refactor  [FixRM #8690]

The PSEXEC module doesn't use the PSEXEC mixin. Nor does psexec_loggedinusers.

Fixes an issue where NTLM::UseNTLMv2 wasn't being set for some modules (it defaults to True when its mixed in properly, but is nil if not) often causing login failures on later OS's

~~N.B. This doesn't fix anything to do with RM8698 or 8690. Need to investigate why they dont get shown by chained includes but setting them works:~~

## Verification
- [x] PSEXEC modules show the correct options and advanced options (e.g. NTLM)
- [ ] PSEXEC versus x86
- [x] PSEXEC versus x64 (nb this may not work until https://github.com/rapid7/metasploit-framework/pull/2661)
- [x] auxiliary/admin/smb/psexec_command still works
- [x] auxiliary/admin/smb/psexec_ntdsgrab still works
- [x] auxiliary/scanner/smb/psexec_loggedinusers still works
- [x] exploit/windows/smb/psexec_psh still works