Minor issues arising from unpacking combined_table

[ehwenk]

While recreated the relational table structure from the combined table, some minor issues are arising that make it impossible to recreate the original table with information in the same sequence:

• link_vals in the contexts table aren't being arranged in order before being merged together. That is you can get 3, 1 instead of it always being 1, 3
• the methods aren't alphabetised in the methods table
• in the methods table, traits and methods might appear even if there are no trait measurements/values for these traits. This is maybe appropriate if all values are excluded?