Add some (macro) file operation wrappers

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

src/fileops.h

@@ -47,6 +47,10 @@ extern off_t gitfo_size(git_file fd);
 extern int gitfo_read_file(gitfo_buf *obj, const char *path);
 extern void gitfo_free_buf(gitfo_buf *obj);
 
+#define gitfo_unlink(p) unlink(p)
+#define gitfo_mkdir(p,m) mkdir(p, m)
+#define gitfo_rmdir(p) rmdir(p)
+
 /**
  * Read-only map all or part of a file into memory.
  * When possible this function should favor a virtual memory