Added readfilebytes and writefilebytes

These methods are like readfile and writefile, but don't treat the
output/input as unicode respectively.

CHANGES.txt

@@ -4,6 +4,7 @@ CHANGES
 master
 ------
 * PATENTS: Updated to version 2 (http://fb.me/patents2)
+* fileutils: added `readfilebytes`, `writefilebytes` for raw binary bulk IO
 * SelectTask: play more nicely with frameworks that steal sys.stdout
 
 0.7.2

sparts/fileutils.py

@@ -17,15 +17,23 @@
 
 
 def readfile(path):
-    """Return the contents of the file at `path`"""
+    """Return the contents of the file at `path`, as a string"""
+    return readfilebytes(path).decode('UTF-8')
+
+def readfilebytes(path):
+    """Return the contents of the file at `path`, as bytes"""
     with open(path, mode='rb') as f:
-        return f.read().decode('UTF-8')
+        return f.read()
 
 def writefile(path, contents):
-    """Write `contents` to the file at `path`"""
-    logger.debug('writefile("%s", ...)', path)
+    """Write string `contents` to the file at `path`"""
+    writefilebytes(path, contents.encode('UTF-8'))
+
+def writefilebytes(path, contents):
+    """Write bytes `contents` to the file at `path`"""
+    logger.debug('writefilebytes("%s", ...)', path)
     with open(path, mode='wb') as f:
-        return f.write(contents.encode('UTF-8'))
+        return f.write(contents)
 
 def makedirs(path, *args, **kwargs):
     """Create necessary directory heirarchy to `path` if it doesn't exist"""