Adding DataPoints back in...

To avoid the memory leak, fill the DataStream with DataPoint objects. As
new data is added, it overwrites the DataPoint member variables rather
than the DataPoint object itself. Therefore, no DataPoint object will
need to be deleted.
Updated UML diagrams. Added uml config diagram.
Added functionality for the STTDataPoint.

Instead of making a new STTDataPoint every time a measurement is made,
the moisture sensor edits the STTDataPoint's already in the DataStream.
The cyclic ArrayDataStream works nearly the same, just uses the
manually_update_next function instead of the add_data function. When the
moisture sensor creates the data stream, the moisture sensor fills the
data stream with empty STTDataPoint objects.
Fixed tabs in all the files!
Merge branch 'master' of https://github.com/eshughes93/Smart-Irrigation-Project