CHANGE drop the template parameters of models, they are often incorrect, missleading and impossible to maintain
FIX Vector/ Matrix concepts have array_type and data() as special properties
- ALL proxy shortcuts are disabled by default as they cannot implement correctly type size_type and difference_type, range and slice
- projection free functions are also able to shortcut proxies of proxies
dense_vector/matrix_concept did not yet have any difference from the container concepts and could be removed
The differences between dense and sparse can be added again later
