Updated gtest to 1.7
Mac OS X Clang fix in logog.

https://github.com/johnwbyrd/logog/commit/a2ab4643ea4abc9df7a91a60cc60b902cca576fb
fix clang compiler errors on os x. need to add +=,-= operators in DenseVector class
Merge pull request #5 from norihiro-w/clang33-fix

fix clang compiler errors on os x. need to add +=,-= operators in DenseVector class
fix an compiling error on xcode. CMAKE_BUILD_TYPE is not available.
fix segmentation faults in +=, -= operators
Merge pull request #6 from norihiro-w/clang33-fix

fix erros
Merge pull request #253 from bilke/clang33-fix

Fixes for Clang 3.3 on Mac OS X 10.9