Floris

Update power loss in yaw for above rated according to method in Optimising yaw control at wind farm level by Ervin Bossanyi

Small fixes to ct calculation, and cp in low wind speeds

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Released on 2019-05-31

Visualization:

- Add quiver plot function to show in-plane flows
- Adds example 7 which visualizes curl in the wake

Energy Ratio

- Adds additional functions for computing energy ratio as a function of wind
speed
- Adds an example which uses FLORIS simulation to demonstrate the energy ratio
methods

Wake Model changes

- Set deflection multiplier in gauss deflection to 1.2 (was 1.0) to better
match SOWFA and field results
- Update regression test to match

Small Changes

- Removal of unnecessary imports in some files
- Update of the CP/CT tables for example NREL 5MW ref to better model above
rated
- Fix VEC3 print method to print ints without decimal values

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Released on 2019-05-07

**This update introduces breaking changes to the FLORIS API.**
See the code reference documentation <https://floris.readthedocs.io/en/develop/source/code.html>
for detailed information.

- Adds the Curl wake model (Martinez-Tossas et al)
- Improves the FLORIS object hierarchy
- Incorporates an analysis tools package alongside the simulation package
- Adds examples demonstrating using the ``simulation`` and ``tools`` packages
- Adds in-code documentation via doc strings
- Reworks and expands the online documentation