Add analyzers to detect incorrect usage of Content Managers for vanilla assets

[SinZ163]

This Analyzer addition contains two new analyzers:

1. AvoidContentManagerBadType
   • This will trigger when DataLoader can load the given Data asset, and the type is wrong. This is an error and will cause exceptions at runtime anyway
2. PreferContentManagerDataLoader
   • This will trigger when DataLoader can load the given Data asset, regardless of type. This is Informative as its best practice, but the code will work anyway.