Merge pull request #69 from eile/master

Refactor Barrier API for robustness, deprecate old API
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Merge pull request #70 from tribal-tec/master

Print help always
Fix #71: BufferCache race
Merge branch 'master' of https://github.com/eile/Collage
Update travis config
Merge branch 'master' of https://github.com/eile/Collage
Integrate common CMake stuff using git externals
Merge branch 'master' of https://github.com/eile/Collage
Readd deleted files
Merge pull request #73 from eile/master

Integrate common CMake stuff using git externals
Readd deleted files
Merge branch 'master' of https://github.com/Eyescale/Collage
Update Travis config
Fix connection unit test
Update Travis config
Merge branch 'master' into rtt

Conflicts:
	co/bufferCache.cpp
Cosmetics