Harmonized Metadata Documentation

[shirey]

Use the {metadata-spec-type}-field-mappings.csv in each assay metadata directory at reharmonize-legacy-metadata repo/metadata/{metadata-spec-type} directories to harmonize the metadata attribute pages.

• Remove version sections (only one section) on the page
• For attributes that aren't available in the most recent version (first column in csv), put these at the bottom of the attribute list and mark as deprecated- where the definition of deprecated is "This attribute is available in older, legacy metadata. Data may exist for this attribute, but is no longer collected for newer data"