Update .travis.yml

Trying a fix to the travis.yml file
Merge pull request #45 from dvinc/master

Various viewer improvements: single instance, figures mgmt, sharper image export
Merge pull request #46 from dvinc/master

New architecture and 2D-projection of N-D objects!
Merge pull request #47 from dvinc/master

Drawing of set of boxes, union of boxes and lines (closes #12) + various improvements
Update vibes.h
Merge pull request #52 from dvinc/master

Support for separate edge and face colors. Named objects.
Merge branch 'master' of https://github.com/nicolaje/VIBES
Merge branch 'master' of https://github.com/ENSTABretagneRobotics/VIBES

Conflicts:
	.travis.yml
Merge pull request #55 from dvinc/master

Groups, Properties and better Zoom
Merge pull request #56 from dvinc/master

Doxygen. clearGroup,removeObject,closeFigure. Renaming of figure,clear,connect,disconnect in API
Merge pull request #57 from dvinc/master

Improved axis control, implemented axisLabels. Breaks compatibility with "view" messages.
Updated .pro file
Merge branch 'master' of https://github.com/ENSTABretagneRobotics/VIBES into ADDING_ROBOTS
MATLAB Client API preview should be on the repository
Update drawing_3D.m

Changed x step from 0,1 to 0,01 to respect the code in the article.
Update drawing_3D.m
Merge branch 'master' of https://github.com/ENSTABretagneRobotics/VIBES
Vibes state variables are now in anonymous namespace
Added a lacking <cstdlib> include (for rand()) to the all_commands.cpp example.