Log Message:
Update libbson to 0.8.2.

Changes in 0.8.2
----------------
 * A fix for BCON when used from C++.
 * Change bson_next_power_of_two() to accept size_t. This should not be
   an ABI break since it is static inline.

Changes in 0.8.0
----------------
This cycle includes much, much more documentation for your perusing. There is
much more cross-referencing and structure for your navigation pleasure.

We've improved support for Libbson on a few more exotic platforms. SPARC
support is looking pretty good these days.

You'll also find some new examples in this release to help you get started a
bit faster. If there is something you'd like to see, just ask!

There are a few ABI breaks this cycle, as we are well on the road to a 1.0 and
would like things as clean as possible. I anticipate a few more during the next
couple of cycles, but we will try to keep them to a minimum.  With that said,
you *WILL* need to recompile your application against 0.8.0.