Refactor combinatorial sample to reference library

[hampusnasstrom]

Currently the CombinatorialLibrary is a Collection which contains references to all the samples. After discussions with @RoteKekse we decided to try to instead make CombinatorialLibrary a CompositeSystem and have the Combinatorial sample reference the library instead. This makes it so that adding a sample does not need modifying the Library.

• [ ] Change CombinatorialLibrary inheritance
• [ ] Change reference direction
• [ ] Add summary plot to library
• [ ] Deal with discreet libraries
• [ ] Test HTEM
• [ ] Test HZB classes (Unold lab)