Trajectory CSV files with orientations (Feature #91)

CSV files with orientations:

• Added Trajectory.h that describes a trajectory of positions and orientations.
• TrajectoryCSVWriter (formerly csvwriter) now uses this new Trajectory type. Thus, UMANS now adds agent orientations to CSV output.
• Added TrajectoryCSVReader as well, to read a CSV file or a folder of CSV files. It is currently not used, but it may be useful in the future.

Closes #91 (closed)

added feature label

added 4 commits

• d3851a34...d12b398a - 3 commits from branch master
• b247d0f4 - Merge branch 'master' into 91-orientations-csv

Compare with previous version

mentioned in commit 7b9843ac

merged