Adding qualifiers to tbl_sample_dimensions and tbl_sample_group_dimensions

[MattiasSealander]

During preparation of dendrochronological data the need to store measurements/dimensions on a sample level that includes ranges/intervals, min/max values, etc. became apparent. Rather than storing these as text descriptions they should be stored in as sample/sample group dimensions, but these tables lack the function to store such data, aside from adding dimension types that are also qualifiers.

Linking tbl_sample_dimensions/tbl_sample_group_dimensions to the new tbl_value_qualifiers will alleviate some of these issues and make it possible to store a greater range of measurements/estimations of dimensions.