Split node packages

[liamhuber]

• Deprecate (and hide) the older nodes
• Split those that remain into multiple modules
• Make pyiron_atomistics the default module on GUI instantiation

[github-actions[bot]]

:point_left: Launch a binder notebook on branch _pyiron/ironflow/split_nodepackages

[coveralls]

Pull Request Test Coverage Report for Build 4986287753

• 102 of 228 (44.74%) changed or added relevant lines in 8 files are covered.
• 2 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-10.6%) to 50.736%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
ironflow/nodes/array.py	37	51	72.55%
ironflow/nodes/standard.py	23	43	53.49%
ironflow/nodes/plot.py	35	79	44.3%
ironflow/nodes/deprecated/flow_control.py	0	48	0.0%
<!--	Total:	102	228	44.74%	-->

Files with Coverage Reduction	New Missed Lines	%
ironflow/gui/workflows/canvas_widgets/flow.py	1	64.8%
ironflow/model/node.py	1	68.5%
<!--	Total:	2		-->

Totals
Change from base Build 4985441295:	-10.6%
Covered Lines:	1860
Relevant Lines:	3666

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💛 - Coveralls