Fix compilation after mozilla/rust#9896
Use u8 vecs, not strs. Paths are not always utf8.
Merge pull request #5 from MicahChalmer/size_of_sys_to_mem

Fix compilation after mozilla/rust#9896
Merge pull request #4 from MicahChalmer/nonutf8

Use u8 vecs, not strs. Paths are not always utf8.