Also in this change set: a fix for the packagemaker path on Leopard.
This change set adds support for character literals in Nu. Character literals are single characters or escape sequences enclosed in pairs of single quotes ('). The same escape sequences are supported for character literals and strings. Internally, a character literal is represented by an NSNumber with the appropriate unicode value. This is the same value and type that is returned by the NSString characterAtIndex: method. A new test was added to show a variety of character literals. Testing revealed that the test assertion macros were not hygenic. This change set contains changes to fix this; name assignments inside the test assertion macros now use generated symbols. Also, a few Nu tools were modified to use the new character literal syntax.