Making build process more platform independent...

There is more incompatibility over the use of trailing / in directory names as mentioned in prior commit dbaf85d1df0e4c693c807d2a06a091c339cbc101

I've alleviated this by adding a grep filter to the find command for *nls* directories (line 83) such that the src/dojox/grid/nls/ is not copied prior to the full src/dojox/grid/ copy requested in line 85. Not sure why this fails, but keeping directory trees specified once is alleviating the problem. I can now cut released on Debian systems once more.