Attempting another way to remove duplicate vessel bug

Courtesy of jdmj;
https://github.com/Cilph/RemoteTech2/issues/189#issuecomment-31704703
Yep, looks like per-frame caching will have to go for now
Merge branch 'alternate-duplication-bug-fix' into develop
Merge pull request #13 from warrenseymour/develop

Develop