Gizzard Shad Cleanup

[madMatchstick]

Bringing over Todos from PR #43

1. Some of these ideal SI vars need to be clipped to more logical domain?
   • SI1, SI4 - water quality
   • SI5 - water depth
   • SI6 - tributaries or upper end of reservoir
     consider forcing _shape to hec-ras domain to start?

2. Clean up calculate_si_7() for error (invalid or null) catch
3. Expose each component (reproduction, water quality, food component) outside calculate_overall_suitibilty() so they can be accessed directly from the HSI class
4. Complete SI logic for non HEC-RAS H&H model inputs

[dmragar]

1. Domain masks (hydrologic & vegetation) for HSI and SI vars in the works in dr-in-progress #48

[madMatchstick]

2. Error catch added in dr-in-progress #48