addGate changes to population names are not reflected in node names

[yannabraham]

When importing gatingML files, in constructTree, special characters in gate names (popName, thisGateName) are replaced with : when the node is added through addGate but this change is not reflected in nodeData, which leads to errors when applying the parsed tree to data.

I used the following temporary fix

gsub('\/',':',popName)

But without knowing exactly which characters are replaced by nodeData it is difficult to come up with the correct regex pattern. I'm happy to submit a pull request if you can provide me with this information.

[mikejiang]

Can you provide traceback output? Also it will be helpful to provide the example xml or at least the example xml node that triggers the error. It's difficult for me to guess the cause or reproduce it without further details of your code