[filesystem][xpressive] Hotfix patches available for 1.36.0

Hotfix patches are available to fix Boost.Filesystem and Boost.Xpressive 
[1.36.0] problems. See 
https://svn.boost.org/trac/boost/wiki/ReleasePractices/HotFixes

Providing hotfix patches is something new and experimental for Boost. 
Please let us know if you find the patches useful or have other comments.

Thanks,

--Beman