Abstract classes created for curves and controllers.
Generic curve class (meant basically for time and valve cd)  created and working.
Set time series controller class created and working.
Inline valve  class created and working.
Input parser updated to reflect these changes.
Problem class updated to reflect boundary conditions returning multiple heads and multiple flow rates, as opposed to just one head and multiple flow rates.

Small issue with oscilations detected in the beginning of transien calculations. This needs to be investigated.