Add suport for light bundles in clustering

[brettviren]

The output of Q-L matching is a "bundle" which associates charge clusters and light information. Some clustering functions that refine the clusters using this information are not yet ported. To prepare for porting these functions the following is needed:

• Write down data schema for "bundle" and "flash" data based on ROOT files from WCP. (@lastgeorge will provide)
• Implement representation of "bundle" and "flash" in WCT.
  • The representation will depend on the actual schema but initial understanding implies bundle information can be represented by the PC tree.
• Implement an I/O mechanism in WCT to load "bundle" and "flash" in addition to the blob information so that it is available in a clusterring function.
  • Eventually this loading must take into account a WCT Q-L matching component running but initially comes from the ROOT "bundle" file.
• Provide Jsonnet config to exercise loading in a job containing MABC.
• Fill in the missing dictionary information (xxx in red color) @ https://github.com/WireCell/wire-cell-toolkit/blob/apply-pointcloud/patrec/docs/porting_dictionary.md