Add some move constructors.
Fix a bug in the stdout logger sink
Merge branch 'develop' of github.com:KayEss/fost-base into develop

Conflicts:
	ChangeLog
Add a missing header.
Fix a test so it's compatible with C++ 11.
Add in loading of requirements.jam file and PROJECT_REQUIREMENTS.
Redesign the thread handling.
Change the output streaming for `fostlib::string` to use the underlying platform implementation
Add in a control macro for visibility of the log builder move constructor.
Try to set BOOST_SPIRIT_THREADSAFE
Small changes:

* Allow a `timestamp` to be coerced to a `boost::filesystem::wpath`
* Make the last parameter to `replace_all` default to `fostlib::null`.
Merge branch 'develop'