ilastik.cmake: On Mac OS, rename the drtile.dylib library to drtile.so, since Python seems to insist on that name.
ilastik.cmake: On Mac OS, rename the drtile.dylib library to drtile.so, since Python seems to insist on that name.

janelia-flyem/buildem,chaubold/buildem,chaubold/buildem,chaubold/buildem,janelia-flyem/buildem