Pushed duration service argument through C++ side.
Added tests for scheduler.

These test pass meaning the duration code runs. It still may not be correct though.
Updated and tested FIFO executor. Removed MDP depedency from base executor.

This is now ready for a full release without the MDP parts.
Merge pull request #92 from hawesie/hydro-devel

Moving distance/duration collection out of scheduler and into interface