Changes in YAP-6

Yap-6.0.6:

• FIXED: similar problem in unify_dbterm.
• FIXED: bug in implementation of unify_bigint instruction (obs from Jos de Roo).

Yap-6.0.5:

• FIXED: get rid of L constants (use cast).
• FIXED: outputing inf and nan in WIN32/64 (obs from Paulo Moura).
• NEW: WIN64 port.
• FIXED: improve SWI frame handling.
• FIXED: stack expansion could rewrite doubles and big ints.
• FIXED: unsafe test for attvar could crash.
• FIXED: rbtree doc (from Jan Wielemaker).
• FIXED: trail marking should be careful to reset attvars to attvars.
• FIXED: pl_function_t not function_t.
• NEW: update sgml package to latest SWI.
• FIXED: automatic generation of SWI atoms.
• IMPROVEMENT: better emulation of SWI atom_t and functor_t. Now they can be defined to be a constant.
• FIXED: 64 bit complaints in Matlab interface.