boost/python/object_operators.hpp: added missing error checks in operator bool_type(), operator!(); this resolves https://svn.boost.org/trac/boost/ticket/3356 posted by Stefan Seefeld

[SVN r55708]

libs/python

@@ -1 +1 @@
-Subproject commit d7389277d3a2291036e11d58a122de5c368ee611
+Subproject commit e3f6f015881514440a800575d279c4112cf526b6