Add solver dependent storage macro

[kaipartmann]

The macro storage(material, storage) is now extended with a macro storage(material, solver, storage). This gives the possibility to create a custom time solver that requires new fields that are not added in the general storages.

[codecov]

Codecov Report

Attention: Patch coverage is 65.00000% with 7 lines in your changes missing coverage. Please review.

Project coverage is 91.54%. Comparing base (80b7910) to head (305a113).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
src/core/storages.jl	63.15%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #184      +/-   ##
==========================================
- Coverage   91.63%   91.54%   -0.09%     
==========================================
  Files          44       44              
  Lines        4258     4272      +14     
==========================================
+ Hits         3902     3911       +9     
- Misses        356      361       +5     

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