Allow setting 'raw' attrs on XML for tables to be loaded from hex

Previously one had to set the 'ERROR' attribute.  Accept raw also.
So, for example one can say:

  <cmap raw="1">
    <!-- Hand-coded format13 table mapping all Unicode
         characters to .notdef glyph. -->
    <hexdata>
      0000 0001 <!-- version numTables -->
        0000 0006 <!-- platformID encodingID -->
        0000000C  <!-- offset -->
          000D 0000 <!-- format reserved -->
          0000001C  <!-- length -->
          00000000  <!-- language -->
          00000001  <!-- nGroups -->
            00000001  <!-- startCharCode -->
            0010FFFE  <!-- endCharCode -->
            00000001  <!-- glyphID -->
    </hexdata>
  </cmap>
diff --git a/Lib/fontTools/misc/xmlReader.py b/Lib/fontTools/misc/xmlReader.py
index 581039d..85dd441 100644
--- a/Lib/fontTools/misc/xmlReader.py
+++ b/Lib/fontTools/misc/xmlReader.py
@@ -79,7 +79,7 @@
 					print(msg)
 			if tag == "GlyphOrder":
 				tableClass = ttLib.GlyphOrder
-			elif "ERROR" in attrs:
+			elif "ERROR" in attrs or ('raw' in attrs and safeEval(attrs['raw'])):
 				tableClass = DefaultTable
 			else:
 				tableClass = ttLib.getTableClass(tag)