[plt-scheme] 299.108

MzScheme and MrEd are now version 299.108 in the SVN repository trunk.

The changes are related to Unicode and SRFI-75:

 * Changed `char-lower-case?' and `char-upper-case?' to match the
   Unicode "Lowercase" and "Uppercase" properties, instead of SRFI-13.

 * Added `string-upcase', `string-downcase', `string-titlecase',
   `string-foldcase', and `char-foldcase'.

 * \U in strings and characters allows up to 8 digits (again) instead
   of 6.

 * In case-insensitive mode, symbols are case-folded instead
   of downcased (usually the same thing, but not always).


Matthew