Log: Remove obsolete MSVC version checks.

[SVN r85931]
Fixed #9155.

[SVN r85965]
Minor code cleanup.

[SVN r85967]
Fixed #9160.

[SVN r85982]
Added Date keyword.

[SVN r86014]
Fixes for building with Clang on Darwin.

[SVN r86147]
Optimized compile times and reduced binary size. Hopefully, this will resolve linking timeouts in the tests.

[SVN r86148]
Removed unneeded include.

[SVN r86149]
Removed the workaround for ticket 8642 as it doesn't really help but just covers the problem. Attempt to avoid using codecvt() from Boost.Filesystem instead.

[SVN r86150]
Fixed parsing RotationTimePoint parameter values from settings, when the time point only included time of day (i.e. daily rotation).

[SVN r86225]
Added a FAQ entry about problems with file sinks on process termination.

[SVN r86296]
Performance optimizations for Haswell.

[SVN r86319]