add new spinup option for idealized experiments

[pat-schmitt]

Here I add some new spinup options, relevant for the idealized experiments.

[coveralls]

Pull Request Test Coverage Report for Build 5461803280

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This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 104 of 156 (66.67%) changed or added relevant lines in 7 files are covered.
• No unchanged relevant lines lost coverage.
• Overall first build on add_new_spinup_options at 64.198%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
combine1d/core/cost_function.py	55	58	94.83%
combine1d/sandbox/individual_experiment_dashboard.py	0	49	0.0%

Totals
Change from base Build 5356109519:	64.2%
Covered Lines:	2132
Relevant Lines:	3321

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💛 - Coveralls

[pat-schmitt]

Here I added two new options for the initialisation of the model:

1. the possibility to start from the perfectly known initial state (for testing with idealized experiments'
2. the possibility of using the initial ice volume at each grid point as control. For this, I also added a new regularisation term which prefers a smooth initial ice flux at the start of the modelling time. The idea is that with this new control, the algorithm has many degrees of freedom and by favouring a smooth initial flux I want to minimise the effect of an initial shock. So I tell the algorithm to start from a dynamically more consistent state.