This PR adds the capability to read also HepMC3 formatted files. The change was straightforward where the reading was concerned, extracting the version and propagating this information to the reading was a bit more tricky. I hijacked the FindFirstEvent() method for this which is called before the processing. It reads now the first line, extracts the version and sets a flag which is later used to instantiate the specific reader.
This PR adds the capability to read also HepMC3 formatted files. The change was straightforward where the reading was concerned, extracting the version and propagating this information to the reading was a bit more tricky. I hijacked the FindFirstEvent() method for this which is called before the processing. It reads now the first line, extracts the version and sets a flag which is later used to instantiate the specific reader.