[12gevmoller_sim] [JeffersonLab/remoll] f51eda: Use doctype->getentities to parse over entity loca...

[Wouter Deconinck]

  Branch: refs/heads/bugfix-issue-254-save-xml-files
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  Commit: f51eda6af4937a458a7d55af69b2ec6e62c8fa16
      https://gcc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2FJeffersonLab%2Fremoll%2Fcommit%2Ff51eda6af4937a458a7d55af69b2ec6e62c8fa16&data=02%7C01%7C12gevmoller_sim%40jlab.org%7C7c0ff023774041f6cf0108d6bdbdd945%7Cb4d7ee1f4fb34f0690372b5b522042ab%7C1%7C1%7C636905020423140155&sdata=k0LDZ3iar11N7YyZe%2BsIOVgLIibG1bHKNdi2fKPiC80%3D&reserved=0
  Author: Wouter Deconinck <wdconinc at gmail.com>
  Date:   2019-04-10 (Wed, 10 Apr 2019)

  Changed paths:
    M src/remollIO.cc

  Log Message:
  -----------
  Use doctype->getentities to parse over entity locations

Now we just need to combine systemId and docURI into a filename:
```
docURI:
file:///home/wdconinc/git/remoll/geometry/mollerMother_merged.gdml
entity: solids/world.xml
entity: positions.xml
docURI:
file:///home/wdconinc/git/remoll/geometry/target/subTargetRegion.gdml
entity: ../materials.xml
entity: ../matrices.xml
```
Once we have a filename as absolute path we can check if it is alredy
being stored, then store it if not.