Packages and Attributes [HB 2]

Bug fixes:

• A bug with package require statements which would often cause `Source not available' to be printed erroneously has been fixed.

New features:

• New procedure ListAttributes to list the valid attribute field names for structures belonging to a given category.
• New function GetAttributes to return the valid attribute field names for structures belonging to a given category as a sorted sequence of strings.
• New verbose flags may now be created by the user within packages by a declare directive such as: declare verbose MyFlag, 3; (the 3 gives the maximum level).