remove artist -> user assoc

remove artist?
change to owner?
drop asset_owners

layout helper accept xs, sm, md, lg
change to site & client revenue from artist & owner
royalty_keep moved to asset
implement action_cog

fix destroy asset_detail
remove asset_owner_id from assets
moderators, clients datatable
fix ability client_id
fix asset_detail ability
clients have revenue

bs_col can push / pull sm, md, lg
revenue tables

link_if_can
fix rake db:clear and flush and push_settings
remove breadcrumbs home icons
breadcrumb home icon
Merge branch 'owner'