[BUGFIX] Improve handling of multidimensional turbine conditions

[misi9170]

This pull request provides various bug fixes to the multidimensional turbine code. In particular, it allows users to specify the multidim_conditions as a keyword argument to FlorisModel.set(). Additional bug fixes include the ability to use a single condition and updates to the multidimensional turbine documentation (and turbine documentation more broadly).

Related issues:

• Complete multi-dim code #989 This PR directly addresses this issue
• Allow TI to impact turbine power production #785 The turbulence_intensities keyword argument in FlorisModel.set() will still not access the multidimensional code; users will need to specify turbulence intensity separately in the multidim_conditions. This is as far as we will go with this, and I will consider the issue addressed. See Complete multi-dim code #989 for more discussion.
• Bug with multi-dimensional Cp - Ct table #1118 This PR directly addresses this issue by allowing a single condition.
• Floating IEA 15MW data #1130 Values are currently fictional. I will establish a new issue to provide real values.
• Documentation error in the Turbine Input File Reference #1125 Updates made to the turbine documentation to improve information about floating and multidimensional turbines and the turbine library and to provide clarity on fictional values.
• Bug report: TurbineInterface not covered in tests and examples #901 As part of reorganizing the turbine documentation, I have removed the use of the TurbineInterface and TurbineLibrary from documentation and added deprecation warnings to these classes.
• [BUG] Update Turbine Input File Reference and Main Input File Reference #1053 As part of reorganizing the turbine documentation, I have cleaned up the Turbine File Input reference and went ahead and cleaned up the Floris Main Input File reference while I was at it.

Related PRs:

• [BUGFIX] Tilt cosine law correction #1126 is also related to floating turbines, but to do with (computationally) how off-reference tilt angles are applied.

Not addressed here

Values given for the IEA 15MW reference turbine for the floating tilt angle and dependency of power and thurst on wave height, wave period, and turbulence intensity are fictional and may be misleading. I intend to open a separate issue to address this in future.

To do

• existing tests pass (in particular, turbine_multi_dim_unit_test.py)
• add new tests for multidim turbine code
• documentation for multidim
• Fill in PR description
• Update turbine library documentation

[misi9170]

I'm now done with code changes (I think), but starting to work on the docs I think this is a good time to go ahead and improve turbine documentation across the board. I plan to add a Turbine "subfolder" to the documentation, and in it place (while reworking):

• Turbine Operation Models
• Floating turbine modeling Documentation error in the Turbine Input File Reference #1125
• Turbine library interface (add deprecation note, possibly warning in code) Bug report: TurbineInterface not covered in tests and examples #901
• (new) multidimensional Cp/Ct definition information Bug with multi-dimensional Cp - Ct table #1118
• Turbine input file reference [BUG] Update Turbine Input File Reference and Main Input File Reference #1053, Documentation error in the Turbine Input File Reference #1125

[misi9170]

After discussing with @dzalkind , I've decided that in this PR, I will include the bug fix for specifying multidimensional input conditions but not yet update reference values for the floating IEA 15MW turbine. In the mean time, I have updated various pieces of the documentation for floating turbines and indicated that the floating tilt table, along with the dependency of the thrust coefficient and power curves on wave height and wave period, should be treated as fictional. I will indicate this decision in related issues and discussions.

[paulf81]

This could be a prior issue, but shouldn't the magenta dashed line be on top of the blue line in the 0th axis?

[misi9170]

I think this is currently correct. The idea here is that the black line represents the fixed-bottom NREL 5MW; the blue line represents what happens if you took the fixed NREL 5MW and put it on a floater (with a fictional level of added tilt for different wind speeds); and the magenta dashed line is the (fictional) case where the NREL 5MW power and thrust coefficient is defined as being on a floating platform, so no tilt correction to the power and thrust curve should be applied (as the effect of tilt is already inherently included).

[paulf81]

I reviewed and ran the tests and went through and ran all examples. I reviewed all the code and docs and all looks good to me. Left a few minor comments