Testing the parsetree fails on Windows because the .ml files have `\r\n`
endings. For these tests, simplest simply to ensure that they are checked
out using LF endings, even on Windows.
I'm not familiar enough with Subversion to know how properties work
there, but the translation for detecting binary files to git using
attributes is incorrect. Checking for the binary attribute with
check-attr only detects if the file has been *specified* as binary.
Script altered to use a "well-known" plumbing command to detect whether
git regards a particular file as binary. This takes into account
.gitattributes, but also works if the file has been automatically
detected as binary by git.