add minimum buffer size
Merge pull request #854 from sijchen/bufferlencheck_fix

It is OK for this bug
Clarify a comment about MSVC parameters to fix building gtest

The temporary bug in gtest has now been fixed, but we still can keep
using the current way of fixing MSVC 2012 builds instead of switching
to the solution used previously.
Merge pull request #856 from mstorsjo/clarify-comment

Clarify a comment about MSVC parameters to fix building gtest