Compatibility with updated third-party libraries

[martinruenz]

Changes in this pull request aim at a better compatibility with updated external libraries (glog and sophus).

• Sophus renamed some classes and commit 6a34461 reflects these changes
• The preferred way to include CMake packages is to use "Config" mode. It is not necessary to specify GLog_INCLUDE_DIR and GLog_LIBRARIES anymore, making FindGLog.cmake obsolete. See Set GLOG_FOUND, GLOG_INCLUDE_DIR and GLOG_LIBRARY variables in glog-config.cmake.in google/glog#133 This is reflected in commit e65267c

[ArthurGodoy]

Hi @martinruenz, I am trying to build your branch on a Ubuntu 16.04 machine with latest Sophus and I am getting this error:
typedef EIGEN_DEPRECATED SO3Group<double> SO3; ^ In file included from Calibu/include/calibu/cam/camera_xml.h:28:0, from Calibu/src/cam/CameraXml.cpp:24: Calibu/include/calibu/cam/camera_rig.h:65:23: error: ‘Sophus::SO3 {aka Sophus::SO3Group<double>}’ is not a template rdf * Sophus::SO3<Scalar>(rig->cameras_[c]->RDF()).inverse();

There is anything I can do to resolve this?