fix adding new claims - cause_support input field added to the form

fix lint

claims view layout

remove positions view

remove claim types

implement database migration using flywheel

lint fixes

move env vars to one place; skip moderation queue in demo mode

remove home link

remove "my account" link; disable watching parties

notify user about a new claim when it skips moderation queue

add ability to delete(delist) valuation groups

groups must have owners; add ability to add groups; add ability to add and remove valuations to/from groups

add dropdown component

add pagination to causes