Expression Resources consolidation

[sdash-github]

Need to consolidate expression resources. Old from Wei's analysis. Conekt. arahy1 external resources (if making a separate page for expression resources.

[sdash-github]

DE from Wei.
NFCore output served as webpage (adf) with interactive graphics.

[sdash-github]

UPDATE:

• https://dev.peanutbase.org/expression/ now lists all the expression resources at pb-jekyll site. Corresponds to legacy page, https://peanutbase.org/gene_expression)
• So, now there is an expression dir with index and corresponding yaml in _data/
• Expression item added to Tools under MISCELLANEOUS subheading

Not yet into git repository.
Requesting persusal: @svengato and @adf-ncgr

Notes:
-- https://peanutbase.org/gene_expression/atlas to https://dev.peanutbase.org/expression/expr_tissue_Hyp.html
-- https://peanutbase.org/gene_expression/atlas_nematode to https://dev.peanutbase.org/expression/expr_nematode_DurSte.html
-- https://peanutbase.org/gene_expression/atlas_drought to https://dev.peanutbase.org/expression/expr_drought_DurSte
-- Yet To Be Ported: https://peanutbase.org/gene_expression/atlas_symbiosis
-- Omitted: https://peanutbase.org/gene_expression/atlas_combined (mapped to aradu+araip combined)