[Doc] removed old docu

Documentation/ProjectFile/boundary_condition/UniformDirichlet/t_value.md

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Documentation/ProjectFile/boundary_condition/UniformNeumann/t_value.md

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Documentation/ProjectFile/boundary_condition/UniformRobin/c_UniformRobin.md

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Documentation/ProjectFile/boundary_condition/UniformRobin/t_alpha.md

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Documentation/ProjectFile/boundary_condition/UniformRobin/t_u_0.md

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Documentation/ProjectFile/boundary_condition/t_geometrical_set.md

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Documentation/ProjectFile/boundary_condition/t_geometry.md

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Documentation/ProjectFile/boundary_condition/t_type.md

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Documentation/ProjectFile/initial_condition/MeshProperty/c_MeshProperty.md

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Documentation/ProjectFile/initial_condition/MeshProperty/t_field_name.md

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Documentation/ProjectFile/initial_condition/Uniform/c_Uniform.md

-A uniform initial condition is constant in time and space.

Documentation/ProjectFile/initial_condition/Uniform/t_value.md

-The given floating point value will be set as initial condition for the
-respective components on the entire domain.
-
-Same as values but for variables with one component only.  For multi component
-variables use the \ref ogs_file_param__initial_condition__Uniform__values
-"values tag".

Documentation/ProjectFile/initial_condition/Uniform/t_values.md

-A space separated list of floating point values, one for each component.
-The length of the list must match the number of the variable's components.
-
-The given floating point values will be set as initial condition for the
-respective components on the entire domain.
-
-For single component variables one can _optionally_ use the \ref
-ogs_file_param__initial_condition__Uniform__value "value tag".

Documentation/ProjectFile/initial_condition/t_type.md

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Documentation/ProjectFile/parameter/MeshProperty/c_MeshProperty.md

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Documentation/ProjectFile/parameter/MeshProperty/t_field_name.md

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