Issue 289: filter file names one component at a time

[pbarnes-tibco]

This changes the file name filtering logic to operate on each file name component separately, to avoid conflicts between the escapeString and the file separator. This is a fix for issue #289.

One question I have is, if this PR is accepted, can it get back ported to 3.x? Would I need to do that and submit a PR? And if so, would such a change be made on the origin/maven-filtering-3.x branch?

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