add modal dialog & dynamic form to Batch Actions

thanks to @chrise86 for the updated CSS so this isn't horribly ugly
update CSS so the overlay actually works again
Add note about changing the permitted params key

[skip ci]
Add note about disabling CRUD actions [docs]

[skip ci]
Add `id_column` into the docs

[skip ci]
hide blank slate link if the user doesn't have 'create' permissions

fixes #2588
Ensure multiple attributes_table alternate properly

When there are more than one attributes_table_for being rendered with an
odd number of records, the alternation will be out of sync. Now the
alternation cycle is reset each time.
Remove extra spacing below checkboxes filter
update 1-general-configuration.md to use GFM
Daxter is now seanlinsley
0.6.2 has been released
run pimpmychangelog
fix 0.6.2 compare URL in CHANGELOG
resync docs with YARD docstrings
add better warning to prevent direct editing of auto-gen docs
correct div.class wrapping of searchable filters
update menu docs as per conversation in #2397
copy update for 2-resource-customization.md
convert 2-resource-customization.md to GFM :octocat:
simplify examples in 2-resource-customization.md