dump command - support GUID

[SkowronskiAndrew]

Add support to the dump command to print UnityEngine.GUID as a single hex string. The current output is very hard to work with, because it prints each 32 bit value individual.

        sourceAssetGUID (GUID)
          data[0] (unsigned int) 3418958961
          data[1] (unsigned int) 1234290355
          data[2] (unsigned int) 2387373188
          data[3] (unsigned int) 291235581

What we want is something like the yaml output:

sourceAssetGUID: f778ae0076321f44ab2c21fcaac7036e