Update OpenMesh to get VS2015 Update 3 fixes

9 jobs for VS2015_OM_fix in 80 minutes and 14 seconds
Status Name Job ID Coverage
  Test
passed clang-c++11-Qt4 #6965
Linux MultiThreads

00:06:59

passed clang-c++11-Qt5 #6969
Linux MultiThreads

00:09:24

passed clang-c++98-Qt4 #6967
Linux MultiThreads

00:06:06

passed clang-c++98-Qt5 #6971
Linux MultiThreads

00:06:47

passed cppcheck #6972
Linux MultiThreads

00:34:13

passed gcc-c++11-Qt4 #6964
Linux

00:04:54

passed gcc-c++11-Qt5 #6968
Linux

00:04:43

passed gcc-c++98-Qt4 #6966
Linux

00:03:35

passed gcc-c++98-Qt5 #6970
Linux

00:03:27