Correct addon installation. Do a git pull if directory exists.
Correct also bad function ordering.
Update README.md
Update usage message
Fix #33 and #34
Fix #32
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Fix #35
Override PROJECT_CXX et PROJECT_CC to compile on Ubuntu Travis CI
Merge branch 'master' into per-object-ui-implementation