CAROLINE-5: Add protobuf to the third_party.
CAROLINE-5: Add travis ci config.
CAROLINE-5: Make protobuf library static.
CAROLINE-5: disable opencv checkout.
CAROLINE-5: Fix compilation.
Merge pull request #90 from it-workshop/wp/CAROLINE-5/1

Wp/caroline 5/1
Fix lint_all.py.
CAROLINE-18: remove build cycled dependencies.
Merge pull request #96 from it-workshop/wp/CAROLINE-18/2

CAROLINE-18: remove build cycled dependencies.
#73: Path service for posix.
CAROLINE-9: Add path service. Add singleton. Add at exit manager.
CAROLINE-9: Rewrite camera calibration unit test.
CAROLINE-9: Add gmock checkout to the .travis.yml.
Merge pull request #89 from it-workshop/wp/CAROLINE-9/1

Wp/caroline 9/1
CAROLINE-1: Adds generic reduce and sapply functions for matrices
CAROLINE-1: Abstract class for metrics added.
CAROLINE-1: Adds some simple metrics and tests.
CAROLINE-1: Factory for metrics added.