Adding isort for the formatting

[JosePizarro3]

Adding some more rules and formatting all files to be more plugin-structure compliant.

@JFRudzinski @ndaelman-hu @Bernadette-Mohr this might affect your branches, when rebasing it can get crazy.

[coveralls]

Pull Request Test Coverage Report for Build 9840868774

Details

• 26 of 43 (60.47%) changed or added relevant lines in 19 files are covered.
• 15 unchanged lines in 15 files lost coverage.
• Overall coverage increased (+0.01%) to 78.879%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/nomad_simulations/schema_packages/atoms_state.py	2	3	66.67%
src/nomad_simulations/schema_packages/model_system.py	2	3	66.67%
src/nomad_simulations/schema_packages/numerical_settings.py	1	2	50.0%
src/nomad_simulations/schema_packages/physical_property.py	2	3	66.67%
src/nomad_simulations/schema_packages/properties/band_gap.py	0	1	0.0%
src/nomad_simulations/schema_packages/properties/band_structure.py	2	3	66.67%
src/nomad_simulations/schema_packages/properties/energies.py	1	2	50.0%
src/nomad_simulations/schema_packages/properties/fermi_surface.py	0	1	0.0%
src/nomad_simulations/schema_packages/properties/forces.py	1	2	50.0%
src/nomad_simulations/schema_packages/properties/hopping_matrix.py	0	1	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/nomad_simulations/schema_packages/properties/fermi_surface.py	1	76.47%
src/nomad_simulations/schema_packages/model_method.py	1	70.94%
src/nomad_simulations/schema_packages/variables.py	1	83.08%
src/nomad_simulations/schema_packages/physical_property.py	1	93.14%
src/nomad_simulations/schema_packages/properties/energies.py	1	75.0%
src/nomad_simulations/schema_packages/properties/band_structure.py	1	80.18%
src/nomad_simulations/schema_packages/properties/forces.py	1	72.73%
src/nomad_simulations/schema_packages/properties/permittivity.py	1	83.33%
src/nomad_simulations/schema_packages/properties/band_gap.py	1	90.2%
src/nomad_simulations/schema_packages/properties/hopping_matrix.py	1	82.76%

Totals
Change from base Build 9836608336:	0.01%
Covered Lines:	1647
Relevant Lines:	2088

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💛 - Coveralls