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Updates to 8 sheets, including db and lightweight-markup

db: filled in the 'python' and 'ruby' sections; rm the 'array' section.
lightweight-markup: rm 'latex' column, add 'asciidoc' and 'org-mode' columns

computer-algebra: filled a few entries in polynomials section
data: rm the 'import and export' section
fortran: added a few apl cells
numerical-analysis: rm 'curve fitting', replaced with 'polynomials'
scripting2: add rubocop cell
version-control: fill in somes cell re: git submodules